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Latest tips
*(on deerproofing, from a gardener in Canada): I've
had good
luck with just sprinkling the plants directly with cayenne or hot chili
spice. Also I drape plants with cilantro, lavender and
yarrow.
Deer wont eat anything with those on them.
*The latest on bug zappers, and why you shouldn't
use them (from
Entomological News, 107(2):77-82)
"Our survey of insects electrocuted during routine use of electric
insect traps revealed only 31 biting flies, a minute proportion (0.22%)
of the 13,789 total insects counted. In contrast, species
from 12
orders and more than 104 nontarget insect families, including 1,868
predators
and parasites (13.5%) and 6,670 nonbiting aquatic insects (48.4%) were
destroyed. The heavy toll on nontarget insects and the near
absence
of biting flies in catches suggests that electric insect traps are
worthless
for biting fly reduction - and probably are counterproductive - to
homeowners
and other consumers."
*One gardener sent me this website (you'll need adobe acrobat
to read
it: http://www.cfr.washington.edu/research.mulch/myths/hydrogels.pdf),
which warns of potential problems using hydrogels--
those water
absorbing materials which are claimed to reduce watering in container
mixes.
(Iowa)
What plant and
where?
*Will perennials that grow well in sun also
grow in shade? (VT)
*I have heard of hollyhocks referred to as both biennial and perennial. Does this have more to do with the type of hollyhock or the growing conditions? (VT)
*Can you recommend a perennial ID/guide/source book or website?
I need
to ID a few plants (photos needed). If plants were organized by
sun /
shade / leaf color that would also be helpful. (VT)
*I would like to know if you know of
any reference book about perennial
plants that included information concerning their wind tolerance. (NY)
*Why does a garden with too much variety not seem
as complete as one with a set theme? And how can I keep this variety
but give
my garden/landscape a more solid look?
(VT)
*What perennial or shrub would be suitable for planting with
the
use
of cremation ashes? (mid-Atlantic)
*We are looking for a grass
to plant like a
hedge along the driveway. Any
suggestions? (Maine)
*I want to use drought-tolerant
grasses
to minimize upkeep but don't know what to plant next to the neighbour's
cedar hedge which seems to suck the life out of my garden,
which
has full sun for most of day. (Toronto)
*I grow plants from seeds under lights. My columbine
have aphids. Where do they come from? (Vermont)
*How can I grow root-invasive
perennials
such
as mint in the garden? (VT)
*Are there tall grasses or flowers, even vines, I could plant
on
top of a septic leach field to
hide a fence also on
top of the field? (NY)
*I am looking for a tall fast
growing grass
to provide coverage next to a busy road that will stand up in the
winter
too. Do you have any suggestions? (MN)
*Are the blue lupines seen in June in fields all over northern
New
Hampshire and Maine the native lupine perennis or are they escaped
non-native
garden plants? Any good suggestions for blue
native
flowers we can plant? (New Hampshire)
*What kinds of plants can be planted along a non-spring-fed
pond to help keep it clean? This is a large pond , over an
acre, and
I understand that cattails and other plants will help filter the pond
water.
(Vermont)
*Can I plant hostas under
a maple tree?
(Illinois)
*Do you have any tips for creating a winter garden
or caring
for a winter garden in Southern Cal?
(California)
*Can you suggest the best perennials for a seaside
garden in northern California, about 1 mile from the ocean on
a high
peak. There's nothing between my yard and the Pacific Ocean.
It is
quite windy and often damp throughout the summer due to heavy
fog.
(northern California)
* I have a large zone under pine
trees.
I would love to have a shade garden there but have heard that it is
difficult
to get anything but fern to grow in the shadow of pines. Do
you have
any suggestions? (Michigan)
*I have a plant which was sold as "ghost
plant."
I have grown it in my garden and it has white plumes something like
astilbe
but it is about 5 feet tall. Can you tell me what I have and
whether
or not it will perform in dense or filtered shade? (Illinois)
*I'd like a list of new perennials
for this year,
ones that need to be better known. (Pennsylvania)
*I'd like to plant some heather,
do they
need full sun or will they take part shade? (New York)
*Could you recommend some perennials for part
shade, under a drip line of a roof? (New Hampshire)
*What are some plants I can use to attract
hummingbirds to my garden? (Maine)
*Is there such a thing as a perennial that will flower
throughout the summer? Shady and sunny areas.
(Kentucky)
*What are some groundcover herbaceous perennials that would be
salt tolerant? (Vermont)
*I need suggestions for Zone 5 groundcovers that will provide weed
and erosion control on a slope in full sun. The soil has a
mostly clay
content and surrounds a pond. (upstate New York)
*I want to find a list of
perennials suitable
for containers. (Germany)
*What is your favorite
perennial? (Iowa)
*There is a dense shade area
by a corner of
the house with no sun. Hard to find something to grow
here.
Hostas and hydrangea do OK. I would like something else, but
have
had no luck. Could it be the soil? (Ohio)
*I have a retaining wall with springs keeping the soil damp in
front
of the wall. What are some good choices for a shady,
moist soil ground cover? I have had luck with
ferns. (New York)
*What makes 'Blue
Fortune' Anise
Hyssop (Agastache) better than other cultivars?
* What would be a good perennial groundcover
for
wet soil and sunny? (Ohio)
*What are some
perennials I can
plant that will take drought like we've been having this
year? (Massachusetts)
*Where can I find whether
plant ??? is hardy
in my area?
*I am new to the area (any area, I've gotten this question
from
Alabama, Arkansas and Massachusetts among others) and
want to know what to plant, what will grow well, and some designs.
*My
lawn has several birch trees and the grass has turned to moss.
I would
like to gradually replace the grass with flowers and ground cover. Not
too expensively and I would like to do the work myself. I am a new
gardener.
(St. John's, Newfoundland)
*I'm new to growing perennials, and wondered if there is a
good book on color to help me design with them?
(Massachusetts)
Care and Culture
* Can you give people advice on how to remove their invasive seed producing
plants/shrubs in a proper manner? (VT)
*How can I effectively control sucker growth on rose bushes?
(PA)
* My
daffodil and tulip bulbs don't
bloom. They have
plenty of healthy leaves but no blooms. What fertilizer should
I use to produce blooms? (VA)
*A friend of mine is going to give me
some bulbs
that she says are "sprouting" and in pots. Can they still be
planted
outside now? Shouldn't they be planted in the Fall? Would I
let them go
dormant and plant in Fall? Will they live if I plant them in the
ground now? (VT)
*I am
planning on plant a small batch of Salvia May
Night (Salvia sylvestris ‘Mainacht’) this year in one
of the garden beds
on the side of my parents’ house. If I treated it like annual
Salvia and
pinched back the dead flower blooms, would this promote more flowers?
(VT)
*What is the ideal fertilizer ratio
for Brugmansia
aurea?
(CA)
* Is it possible to overwinter English roses in cold climates?
(VT)
*I am interested
in replanting
an
Easter lily and Oriental lily into my garden. Will
they bloom for the
summer? The Easter lily already bloomed and the Oriental lily
is
blooming now (late April). (Illinois)
*How can I maintain
smaller rounded
habit of
Sedum 'Autumn Joy'
and Coreopsis 'Moonbeam'. They are 4-5 years
old. (Pennsylvania)
*I planted some summer
daffodils this
year.
Do I have to dig them up over winter? (Vermont)
* This time of year
(early March) leaves
on
our hellebores
are ugly and detract from the emerging flowers.
Can we cut them off without causing harm to the plant?
(NC)
*We've tried starting
gladiolus indoors
from small bulblets we collected last year. It has been 6
weeks with
no signs of growth. Any tips or clues? (WI)
*You mention to make late-blooming perennials such as asters
and
Helen's flower shorter and more bushy to cut
back by a third.
Is this a third overall from the top down, or thin out a third of the
shoots?
(Vermont)
*Is it better to water daily when plants are in the sun or to water
once a week? (Connecticut)
*We have lots of woodashes.
Can these
be put on the garden without harming it? (Massachusetts)
*When and how do you divide
peonies?
(Michigan)
*I have retrieved some Stella d'Oro daylily
seeds from my son's very successful plants. Now
what do I do
to propagate them? (Illinois)
*I have several coreopsis plants. Should I cut
off the dead blossoms, and if so, where do I make the cuts?
(New York)
*I will be moving from in September. I have 3 favorite
perennials
including hosta and peony I would like to take with me. What is the best
way to transport them. (Ohio)
*I recently bought a Concord Grape spiderwort.
You mention in your article to cut back after bloom when the foliage
gets
ratty. Mine has reached the ratty stage and my question is
how far
back should I cut it? (Vermont)
*Can I use horse manure
mixed with wood shavings
in the garden? (Vermont)
*Books say to cut lavender
back in the spring,
but we live in a cold zone in Vermont and never do. Should
we?
(Vermont)
*If I bring primrose in to give
as Christmas
presents, what do I tell people about their care?
(Toronto)
*It's fall and I am moving
and want to take
my perennials with me to my new house, how do I do this without harming
them? Do I plant them outside or in pots? (Indiana)
*What are some organic
methods of controlling
insects and diseases on herbaceous garden plants? (New York
state)
*I'd like to make some cuttings
of perennials,
how do I go about this? (Vermont)
*I have some small perennials in pots in a hobby
greenhouse. How should I treat them so they will
get cold and
bloom next season? (Toronto)
*How do I improve heavy clay soil?
(Delaware)
*Does the last
time I can
plant perennials depend on how hardy they are?
(Vermont)
*We would like to sow seeds from a hosta,
and don't know how, or what the seeds are. Please
advise. (Vermont)
*I have purple siberian iris,
with what
appear to be seedpods and layers of seeds inside. Is this
correct,
and will this take away from next year's blooms? (New York)
*I have 'Jacob Cline' bee balm
and I would
like to propagate them. What is the best way? (Pennsylvania)
*Will bulbs grow up
through a layer of mulch,
or do I have to open up space for them? (Vermont)
*Can annuals and tender
perennials be overwintered
indoors? (Vermont)
*Our Elijah Blue fescue
has gone to
seed. Do we need to remove the brown seed stems or leave them on?
(Wyoming)
*I would like to know some good, environmentally friendly ways
to
clear out large grassy areas (acres)
to replace with wild flower
seeds.
(Massachusetts)
*Are antidessicants
effective? (New
York)
*I am trying to grow rugosa
roses from seed.
Didn't work last year. Any suggestions? (Maine)
* I received a potted tulip
as a gift. Is
there a way to have the bulb bloom again, what is the procedure?
(Mexico)
*With all this warm weather this
fall, my perennials
are starting to sprout and green up. Should I mulch them, or
leave
alone? (New York)
*compost tip
*I'd like to know when a plant
is done blooming
for the year, like a lily ....can you cut it down or should you leave
it
till it dies off ? (Wisconsin)
*Three years ago I was given a well established peony dug up
from
a friends garden. Last year was the first time it bloomed for
me
- this year, only one flower - the plant is very lush, dark green and
about
3' accross by 3.5' high (no sign of disease). I give it a
light organic
fertilizer once a year and lime it at least once a year. It gets about
4.5 hrs of direct sun during the middle of the day - what
can I do to improve bloom on this peony? (Vermont)
*Two articles from two different Extension Service offices
state
that most perennials do well in pH of
6.6 -7.0.
Another states they generally do best in 5.5-6.5. Can you put this
issue
to rest? (Massachusetts)
*We recently had a devastating
hail storm which
destroyed all of our plants. What is the best way to care for plants
which
have been beaten down is such a manor? Should I cut them back? If so
how
much? (North Dakota)
*I wanted to know if I have to cut
back my Purple
Allium flowers? They are huge, and I don't want to
cut off the
tops if I am not supposed to. (Utah)
*What can I expect from my Baptisia
plant
the
first year (it didn't bloom), and how do I prepare it for winter?
(Masschusetts)
*How can
I overwinter tender perennials?
(Toronto, Canada)
*This
season my wooden stakes rotted.
Is there anything better to use? (Vermont)
*Do you know
what varieties of lotus
might survive moderately cold Dutch winters? (Netherlands)
*I'm a new gardener and would like to grow
some
perennials from seeds. Which would you recommend?
(Connecticut)
*I would
like to grow Lenten Rose (Hellebore)
from seeds to use as a groundcover for shade, since I can't
afford
to buy the expensive plants. How is this done? (Massachusetts)
*With the
mild winter my daffodils starting
coming up early this year. With the late snow and cold, will
they be
injured? (Vermont)
*How can I
eradicate grasses that are growing
among my spreading junipers? (Minnesota)
*How late can I plant
perennials and bulbs?
(several
states including Alabama and New York)
*Should I cut back
perennials in the fall?
*I
didn't cut my perennials back in the fall. Is spring okay? (Ohio
gardener)
*I
didn't get my bulbs planted in the fall. Is early spring okay? (Illinois)
*Do you have any suggestions
for how to keep
up with the weeds? (New Jersey)
What's wrong?
*How do I prevent Genista Broom Moth caterpillars from defoliating Baptisia australis? Ann D, PAThe Tips
*Bug Zappers (10/02): The latest on bug zappers, and
why you
shouldn't use them (from Entomological News, 107(2):77-82) "Our survey
of insects electrocuted during routine use of electric insect traps
revealed
only 31 biting flies, a minute proportion (0.22%) of the 13,789 total
insects
counted. In contrast, species from 12 orders and more than
104 nontarget
insect families, including 1,868 predators and parasites (13.5%) and
6,670
nonbiting aquatic insects (48.4%) were destroyed. The heavy
toll
on nontarget insects and the near absence of biting flies in catches
suggests
that electric insect traps are worthless for biting fly reduction - and
probably are counterproductive - to homeowners and other consumers."
*Compost tip (9/01): a report released this month from Washington State University showed compost had been contaminated with the herbicide picloram. This entered from animal bedding crops or manures from animals which had fed on crops treated with this chemical. It latest for over a year, and through the composting process, with residual damage to desirable plants to which the compost had been applied. The message: make sure your source of commercial compost if not organic is reliable, free of even lawn residues which may contain herbicides.
*Rabbits and Deer (5/02): In upstate NY I've found the best answer to rabbits, dear, cats, eating or digging is to sprinkle ordinary black pepper on plants, it doesn't dissolve and without stiff wind will deter for 2 weeks or so and it's dirt cheap. I've tried all the commercial remedies and this works the best!!!--Judi
*Hydrogels (6/02): One gardener sent me this website (you'll need adobe acrobat to read it: http://www.cfr.washington.edu/research.mulch/myths/hydrogels.pdf), which warns of potential problems using hydrogels-- those water absorbing materials which are claimed to reduce watering in container mixes. (Iowa)
The Questions and Answers:
How do I prevent Genista Broom Moth Caterpillars from defoliating Baptisia australis? Ann D, PA
The caterpillars are very unique looking and they are easy to
identify as genista broom moth caterpillars (Uresiphita reversalis).
Although more common in the southwest, especially Texas, they are known
to exist from Nova Scotia to Florida, west to California and north to
the Midwest. In 2012, a widespread outbreak was reported in Connecticut,
Maryland, Ohio and Tennessee. The defoliated plants reported were
mainly Baptisia, but others reported were all in the pea family. They
can completely defoliate plants. Control options include:
- check frequently in early spring for egg masses and remove them.
The eggs are on the leaves, cream to yellow color, and although
difficult to see, should be visible.
- hand pick for a light infestation.
- use insecticidal soap if the first two steps do not work. This
will suffocate the caterpillars while they are still small in size.
- use labelled insecticides if the above three steps do not work. A
least toxic choice might be Bt var. kurstaki. (answer originally from
Ann D, in PSS123 course)
*Will perennials that grow well in sun also grow in shade? (VT)
Yes, many will grow in shade, or at least part shade (some that grow well in full sun in the north prefer this if a hot climate), BUT they may be more straggly, with weak stems, and often don't bloom as well if at all. Also, some colored-leaved plants may have more yellow or purple leaves in sun, with more green leaves in shade, needing more chlorophyll (the "green" key ingredient in leaves that helps them utilize sunlight). (both Q and A from Avery L as part of my PSS123 course)
*I have heard of hollyhocks referred to as both biennial and perennial. Does this have more to do with the type of hollyhock or the growing conditions? (VT)
Alcea rosea, the common hollyhock, is a biennial plant that flowers in the second year but may have one or two blossoms and plenty of leaves in the first year. The perennial rumors could come from the self-sowing characteristic of the plant New hollyhocks would sprout up in the third year without the gardener spreading more seeds. However, long bouts of dry heat, as well as rust and pests, could kill the plants before reseeding. (both Q and A from Lindsay L as part of my PSS123 course
* Can you give people advice on how to remove their invasive seed producing plants/shrubs in a proper manner? (VT)
Invasive plants indeed have become a concern to gardeners, both root and seed invasive plants. The first step of course is to be aware of what plants may become invasive before buying them, keeping in mind that invasive properties may depend in part on the climate and habitat (such as soils). For existing plants, or ones that have become invasive through seeding already, easiest is to cut back before they go to seed. If not many, they can be dealt with mechanically such as hoe or shovel. For more resources and a list of plants, see the Vermont Exotic Invasive Plants website. http://www.vtinvasiveplants.org/
*How can I effectively control sucker growth on rose bushes? (PA)
Root suckers, or growth from the base of plants, are a notorious
problem with rose bushes as well as some other plants such as lilacs
and sumacs. These shoots arise from roots, often at a distance
from the plants, as the roots grow outwards. Or, they may arise
from the base of plants from below the graft union if plants are
grafted or budded (as are most roses and many lilacs). Often this
suckering is unwanted, and in the case of grafted plants, will produce
a plant different from the one purchased. Control suckers by
cutting them as close to the ground or root stock as
possible. Planting deeper than normal, such as with the graft
union 4 to 6 inches below ground, also may help to prevent suckering.
There are some products available on the market that
inhibit sucker growth. If applied to
suckers shorter than 6" long they will prevent their growth for up to 3
months.
*It appears we have a bad infestation
of leaf minors on our
columbine. What do you suggest to get rid of them? Will the
plants come back next year? Will the ground harbor these insects having
them return next year? (VT)
Leafminers on columbine are a common problem, but luckily shouldn't
affect plant health in the long term. There are some insecticides
you
can use (check labels in your local garden store, preferably for
organic solutions causing little harm to beneficial insects), but best
control is to pick off infested leaves. Check every few days
beginning
with bloom time which is when eggs are laid by leafminer flies and
larvae then begin. There are several generations per summer, so
unfortunately you'll need to keep at it. Check each season beginning
with bloom as these will likely return. Also keep plants well
watered
and fertilized so they can better cope with this stress. If only
a
plant or two, you might try erecting a small tent over plants just
before bloom with a light-weight fabric as used for frosts. This
will
keep the flies from laying eggs but the drawback is you don't get to
enjoy the flowers!
*Can you recommend a perennial
ID/guide/source book or
website? I need
to ID a few plants (photos needed). If plants were organized by
sun /
shade / leaf color that would also be helpful. (VT)
A great question, but unfortunately there is little for this on
perennials, perhaps due to the great variety. Lots of photos in
books and online, but not really organized as you seek. There are
several such
references for wildflowers, with some overlap with garden perennials,
but most are a-z with photos you just have to look through, one of
better being: Armitage's Garden Perennials: A Color Encyclopedia.
Usually is recommended to ask a local expert gardener, extension
office, or a local perennial nursery or complete garden center having
trained professionals.
*I would like to know if you know of
any reference book about perennial
plants that included information concerning their wind tolerance. (NY)
I don't know of such a book or can't find such lists. Basically
for windy sites just consider more dwarf or compact and shorter
selections (or serious staking). Also you can prune taller late
bloomers back by about half mid to late June to result in shorter and
more compact plants. Consider a windbreak from plants, fence, or
a
combination.
*The stems and leaves on my garden phlox have turned white. Not with
mildew but the entire plant is a
whitish yellow. What's happened? (CT)
I think that still may be mildew, it often starts on bottoms of
leaves
turning the tops yellowish, undersides being whitish or grayish.
I'm
not aware of other diseases causing this symptom, unless leaves are
chlorotic from a soil problem like too wet, lack of fertility, or
similar.
*What is the benefit of placing Kelp Meal in soil?
(NY)
Kelp meal serves as a natural source
of many trace
minerals, vitamins, hormones and plant growth regulators. Nutrients are
supplied in a chelated form, which is the form of nutrients that are
most easily taken up by plants and least likely to be made unavailable
by chemical processes occurring in the soil. It has been used for
centuries as a soil amendment that increases soil nutrition and
enhances plant growth. (Answer by David B)
*What causes my Stokes
Asters to get black
blotches on the leaves, along with big "bites" out of them?
(Vermont)
*How can I maintain smaller rounded
habit
of Sedum 'Autumn Joy' and Coreopsis 'Moonbeam'. They are 4-5
years
old. (Pennsylvania)
Often plants too tall or floppy are a sign of too little
light.
Both of these plants in particular grow best in full sun.
Even then
with age some plants, such as the Autumn Joy, may flop.
Plants that
bloom late in the season such as Autumn Joy, Asters, or even tall
garden
phlox may be cut back by 1/3 to 1/2 in early summer. This
will result
in shorter growth with more branching, and generally only slightly
delayed
bloom if at all. This generally wont work with thin stems
like on
the Moonbeam. Make sure this one has full sun, and not too
much fertilizer
or rich soil which can cause tall and floppy stems.
*I planted some summer
daffodils this year.
Do I have to dig them up over winter? (Vermont)
There really are no true daffodils that bloom in summer in the north,
but this name is sometimes used for a South American relative of the
spider
lily which I think it resembles more than a daffodil. Yes,
either
pot these up to bring inside over winter and keep barely moist in a
cool
location. Alternately, you can dig the bulbs once the tops
have died
back from light frost, then store in moist peat moss in a plastic bag
in
a cool, non-freezing location. Pot and begin watering in
spring,
or plant outside after chance of frost is past.
*I like the look of the boxwood-lined herb gardens
but don't think
boxwood grows too well in Vermont, or at least would take a lot of work
to maintain. Any suggestions as to some kind of perennial that might be
used instead to line a small herb and flower bed? (Vermont)
Depending on the microclimate on your property, such as a sheltered
northern or eastern exposure, you might try one of the cultivars of
Korean
boxwood. There aren't a lot of options for hardy perennials
for the
herb garden, chives being one I've seen used for edging. Just
make
sure to keep flowers after bloom to prevent seeding. Lavender
can
be used if a protected site such as in USDA hardiness zone 5. Most
often
I've seen the annuals holy basil or parsley, even lettuces, used.
*What perennial or shrub would be suitable for
planting with the
use of cremation
ashes? (mid-Atlantic)
Such ashes could be sprinkled around a planting, unless illegal as
in some states. In this case they could be used as
fertilizer, similar
to bone meal. The latter often has an analysis of around
1-13-0,
meaning it provides a little nitrogen, but mainly phosphorus, plus some
calcium. Buried in the soil at planting, this can serve as a
slow-release
phosphorus source. However, if planting bulbs or small plants
or
perennials, you might also add some crushed shells or sharp pebbles to
deter digging mammals attracted to the bone smell. Since
small amounts
shouldn't affect soil pH or provide excessive nutrients, most plants
should
be amenable, the choice depending more on personal preference, light,
and
other site conditions.
*We are looking for a grass to plant along
the driveway
like a hedge. Any suggestions? (Maine)
If you want a tall grass (4-5ft), then consider one of the Switch grass
(Panicum) cultivars. Heavy Metal is bluish
with reddish seed
heads. There are several other good blue cultivars, but
Prairie Sky
tends to flop. Shenandoah is shorter, and more red.
Another
group for a great upright effect of similar height is the Feather Reed
Grass (Calamagrostis), Karl Foerster being a popular
and good cultivar.
If in a warmer climate you might consider Fountain Grass (Pennisetum),
about 3ft. There are many good cultivars of Eulalia (Miscanthus),
from 4 to 8ft., which with short and cooler seasons in the
north
do not tend to seed nor become invasive.
*I want to use grasses to
minimize upkeep but don't know what to plant next to the neighbour's
cedar
hedge which seems to suck the life out of my garden, which
has full
sun for most of day. (Toronto)
Since you still have full sun even with the hedge, here are some
grasses
that should tolerate drought or dry soils as created by the roots of
the
hedge (even though some may be listed for better soils). For
shorter
ornamental grasses 2 to 5 ft tall, consider Big Bluestem (Andropogon
gerardii),
Fountain-grass cultivars (Pennisetum setaceum), and Little Bluestem
(Schizachyrium
scoparium). For tall grasses over 5 ft tall, consider
cultivars of
Eulalia (Miscanthus),. Switchgrass (Panicum), Feather Reed Grass
(Calamagrostis),
or Moor Grass (Molinia). For the latter, the clump of leaves
is a
couple feet high, but flower spikes taller.
*What are the most common problems I should be aware
of with soils?
(VT)
If a soil has a problem in our area, it is often too low pH or too
acid soil. This can be corrected by adding lime, according to
the
soil test. A soil pH that is between 6 and 7, 7 being
neutral, is
often best. A soil pH that is too low or too high makes
nutrients
unavailable to the plant. Soil test sampling bags are available from
state
agriculture testing labs, often at state universities, or from garden
centers.
If purchasing inexpensive soil testing kits you can do at home, make
sure
they are new, as old chemicals in such kits can give wrong results.
*I'm just getting into gardening. What are
ten of the most important
items I should have? (VT)
Of course what is useful in one garden may not be in another.
The most useful items to me are a good pair of gloves, such as
goatskin,
that last through the season; a good weeding tool, both for hand use
and
one for standing; a collapsible rake; a good mulching mower
for returning
grass clipping back to the lawn to recycle nutrients and organic
matter;
a good source of compost; a good garden cart; a good wheelbarrow; hat;
suncreen; and insect repellent.
*How can I grow root-invasive
perennials
such as mint in the garden? (VT)
You can of course keep up with the new shoots as they emerge, weeding
often. Easier perhaps is to plant the pot, and sink the pot
in the
ground. Just make sure the roots don't escape through pot
holes (remove
the pot monthly to check for this), or over the top (keeping the lip or
top of the pot above the soil surface will help). You'll also
need
to divide the plant and repot at least yearly, as it wants to spread
and
when confined may weaken or die out. Other root-invasive
perennials
such as some of the loosestrifes (Lysimachia) dwarf (punctata)
bellflowers can be treated similarly.
*How do I keep the neighbors'
cats
out of my flower beds. We've tried all kinds of repellents
such as
pepper, enzyme from the vet, and moth balls (which everyone suggested
first).
When I put out moth balls the next morning I had three cats laying all
over them. They will go back into their own yard before we
have time
to get the water hose out. (TX)
Is there something such as catnip in the bed that they just can't
resist?
Perhaps an organic fertilizer? Try to figure out what is attracting
them
so much and remove it. You might try other repellents such as
predator
urines. Many with pet problems have success using a hose
attached
to a motion sensor you can buy just for this purpose. When
the animal
gets near the hose turns on them. You might also try talking
to your
neighbors, or getting a dog.
*Are there tall grasses or flowers, even vines, I
could plant on
top of a septic leach
field to hide a fence also
on top of the field? (NY)
Best would not be to plant tall (3-6ft) grasses (most are not from
seed but rather divisions) as they may have deep roots that would
interfere
with the leach lines. Often recommended is just lawn, or
annual flowers.
If planting perennials, used those such as yarrow with more shallow
roots.
To hide the fence consider annual vines such as scarlet runner bean or
Black-eyed Susan vine. Many perennial vines such as
honeysuckle or
hops may have deep roots that would interfere with the leach lines as
well.
* This time of year (early March) leaves on
our hellebores
are ugly and detract from the emerging flowers. Can we cut
them off
without causing harm to the plant? (NC)
Yes, late fall through late winter have all been recommended as times
to cut back the old leaves of hellebores which usually flatten out in
winter
and turn brown. Plants usually put on new growth and leaves
with
warmer spring temperatures, growth that should be hardened to possible
late frosts.
*I am looking for a tall
fast growing grass
to provide coverage next to a busy road that will stand up in the
winter
too. Do you have any suggestions? (MN)
Several of taller (usually 3-5 feet) ornamental grasses that supposedly
resist road salt, the main issue along northern roads, and that are
hardy
are the feather reed grass (Calamagrostis acutiflora),
switch grass
(Panicum virgatum), and cord grass (Spartinia).
As
with most grasses, heavy winter snow or ice can knock them down.
*We've tried starting gladiolus
indoors
from small bulblets we collected last year. It has been 6
weeks with
no signs of growth. Any tips or clues? (WI)
The gladiolus "bulb" is actually a modified base of a stem called a
corm, the bigger offsets each fall you dig the new corms, the smaller
ones
the cormels. These may take two or three seasons to produce
flowering
corms. Each year when planted they don't get bigger, but
produce
a corm that is larger. The first year, and maybe the second,
just
expect grassy foliage. Cormels are slow to
germinate. Check
and make sure they are still firm, not rotted, or shrivelled.
Soaking
dry cormels in cool running water for one or two days, then holding in
moist peatmoss, may help hasten growth.
*You mention to make late-blooming perennials such as
asters and
Helen's flower shorter and more bushy to cut
back
by a third. Is this a third overall from the top down, or
thin out
a third of the shoots? (Vermont)
Cut back in early summer, mid to late June in Vermont for instance,
by one third overall. The plants will then branch from below
this
point, meaning a denser habit and not as tall so hopefully not needing
staking. You can cut back even later for even later fall
blooms.
I once cut back a garden phlox in late July, with blossoms
still
in late October even after freezing and frosts!
*I have
hostas with twisted, stunted, and
puckered leaves. Is this normal, or a disease?
(Vermont)
It depends, some varieties show this normally, but there is a
relatively
newly discovered virus that could be the cause, called Hosta Virus X or
HVX (a Potexvirus). Some varieties over the years such as
Eternal
Father, Lunacy, and Leopard Frog actually have their traits due to less
virulent viruses. This virus though causes traits as you
note, and
is highly contagious through contact of infected sap from one plant
with
another. This is commonly spread by hands or tools such as
through
pruning, so make sure to wash in between with antiseptic
soap. As
with other viruses, there are no cures, so infected plants should be
discarded.
Also like many viruses, plants may carry this one yet not show
symptoms,
which makes diagnosis sometimes very difficult. The cultivar
Breakdance
has been reported 100% infected, while commonly infected cultivars
include
Gold Standard, Striptease, and Sum and Substance. Before
buying these,
or in fact any hostas, get familiar with what they should look like,
and
don't buy them if they look otherwise. It is easiest to see
symptoms
on gold and gold-centered plants, which in addtions to those you note,
may include random green mottling, and mottling along the
veins.
Since this virus must be transmitted in sap and living plants, you can
safely plant where an infected plant was removed as long as there are
no
living roots from the old plant. Considered resistant are the
cultivars
Blue Angle, Color Glory, and Frances Williams. Considered
immune
are Bressingham Blue, Frosted Jade, Love Pat, Great Expectations,
Sagae,
and sieboldiana Elegans.
*Are Japanese beetle traps
a good control
for these pests? I've heard both yes and no. (Vermont)
These traps attract beetles using a powerful odor. For this
reason
some recommend placing them upwind from your gardens, so any beetles
you
have will be attracted to it away from your desirable plants.
Keep
in mind that at best only perhaps 75% of beetles will be caught, hence
one reason some don't recommend them as you may end up with
more
beetles and feeding. Beetles will feed along their way to the
trap,
so make sure you keep traps as far from your gardens as
possible.
They are most effective in settled areas when a whole community uses
them.
Keep them emptied often, and change them at least yearly if not more
often,
as the lures inside go stale. The scent of dead beetles may
repel
living ones, so some gardeners pulverize the collected beetles and
spray
on their plants as a control! Least toxic biological controls
include
neem oil, pyrethrin, rotenone, and beneficial nematodes. Make
sure
if using to apply at correct times, read and follow all label
directions
and precautions.
*I have lily leaf beetles. Is there
anything I can do to
the soil to control these beetles? (Vermont)
Unfortunately there isn't much you can do to the soil around plants,
as these beetles may overwinter away from host plants in woods or
such.
Best is to start watching plants almost daily as they emerge in spring
for reappearance of the red beetles. Handpick, or use neem
regularly
which will repel adults and kill young larvae. Hopefully
research
at the Univ. of Rhode Island with biological predators (from Europe,
where
they already effectively control this pest), will yield useful controls
in the near future.
*I have lots of yellowjackets
around
our yard which makes me uneasy gardening. What can I
do? (Illinois)
Bees are actually good in the garden, especially for pollination, and
are seldom a bother unless really provoked. Often
confused
with bees are yellowjackets, which pose a much more serious threat.
Without
barbs on their stingers as bees have, yellowjackets can repeatedly
sting
their victims. They are most active in late summer when their
colonies
reach their peak, and they need higher levels of protein-rich or sugary
foods. Get rid of their most important human source of food, garbage,
and
you'll go far towards getting rid of them. Keep garbage
covered,
and dispose of it frequently. You can also use food to trap
them.
Make traps of one-liter size soft drink bottles. Bait these
with
left over soda, cat food, ham, tuna, or over ripe fruit. Then
place
at the farthest corners of your property.
While working in the garden you can protect yourself from stings with a few simple measures. Avoid wearing brightly colored and patterned clothes. Avoid wearing perfumes and other scents such as from deodorants, scented hairspray, or from suntan lotion. Maintaining your composure around yellowjackets, or if they land on you, also can help prevent stings. Squashing a yellowjacket also releases a chemical alarm that signals others to the area to attack!
Although yellowjackets make paper nests similar to other wasps, they usually build these nests underground. If you notice them flying about your garden, use caution when weeding! Watch for underground nest openings they may be entering and leaving. Using the proper precautions, you can spray these openings in evening and again in morning. Use a wasp and hornet spray that reaches 20 feet, and leave immediately upon spraying.
*Is it better to water
daily when plants
are in the sun or once a week? (Connecticut)
After just planting, you may need to water perennials more often,
especially
if it is dry. Otherwise, and after the first month or two, a
good
soaking once a week is better than more frequent light
waterings.
This helps promote deeper rooting, rather than surface roots that dry
out
quickly. Mulching will help decrease the amount of watering,
as will
lots of compost or organic matter in the soil. Annual flower
are
the opposite--water less when first planted or they may stay too
wet.
Once established, they may dry out quickly and need watering every day
or two if no rain, or light rain. This is especially true if
in containers,
more so if small containers or clay ones.
*What perennials don't moles
eat? (Virginia)
Actually moles don't eat perennials, they eat insects and
earthworms.
It is the voles or meadow mice that are eating garden perennials, in
addition
to grass seeds and stems. Moles have paddle-shaped front feet
for
digging. Voles resemble furry mice with short
tails. There
are some commercial repellent products, and even more home remedies, to
control these. Many of these seem more annoying to humans
than moles
and voles, and are often of little effect. Poison baits are
not recommended
as they can be quite toxic to non-target organisms (humans, pets), and
work their way into the wildlife food chain. The best control
seems
to be traps. I use a mouse snap trap, baited with peanut
butter,
and placed at the opening of an active tunnel. I then cover
the opening
and trap with a clay pot, which is attractive, keeps other critters out
of the trap, and makes the critter think the trap is in the
tunnel.
Traps are most effective in spring and fall when these are most active.
*I'd like to know what perennial summer
flowers rabbits/squirrels
won't eat? (Pennsylvania)
I haven't seen a list of flowers rabbits wont eat, but you might try
interplanting them with plants they don't like the odor.
These include
garlic, onions, Mexican marigold, and dusty miller. If
they're not
too hungry, you might also try sprinkling blood meal, human or dog
hair,
or ground hot peppers around plants. Sometimes soda bottles,
buried
with the tops sticking out (they whistle in the wind) are
effective.
Commercial repellent sprays are often effective, but I've learned you
must
cover ALL parts of the plant (just spray the leaves and they'll eat the
stems!). You can make your own spray with a few teaspoons of
cayenne
pepper, a few drops of dish soap, in a quart of water. Such
taste
and odor repellents may also be effective on squirrels. If
all these
fail for rabbits, fencing is the most effective. Make sure
the poultry
wire mesh or similar is about 18 inches above ground, and at least 6
inches
below ground.
*We have lots of woodashes.
Can
these be put on the garden without harming it? (Massachusetts)
Woodashes act much like lime, raising the pH or alkalinity of the
soil.
Unlike lime, though, they act much quicker so if you add too much the
soil
pH can get too high for good plant growth. Soil pH for most
plants
should be in the 6.0 to 7.0 range. If it is there, you
probably shouldn't
add much or any woodash. If near 6.0 or lower, a safe
recommendation
is 20 pounds per thousand square feet yearly, translating to about a
5-gallon
pail. Since wood ash also adds potassium, and many soils have
sufficient
phosphorus, you may only need to then add additional
nitrogen. A
soil test can tell just what you'll need. Check with your
local Extension
office, Master Gardener program, or state university for such kits.
*When and how do you
divide peonies? (Michigan)
Peonies unlike most perennials really prefer dividing in the late
summer
even through late fall. Unless they are growing too large,
too crowded,
have fewer blooms, or you want plants to move or share, they really can
last many years without dividing. Cut off stems, dig the
clump, and
divide it with your hands or sharp pruners into sections having at
least
3 "eyes" or buds. Then make sure and replant so these buds
are at
the soil surface. Plant too deep, and peonies will grow but
not bloom.
I always like to add a little phosphorus in the hole before planting,
such
as from superphosphate or rock phospate (very little), to aid root
growth.
Water well, and if you mulch for winter, be sure and remove the mulch
in
the spring.
*I have retrieved some Stella d'Oro daylily
seeds from my son's very successful plants. Now what do I do
to propagate
them? (Illinois)
Since daylilies cross so readily (as do many other perennials), there
is no guarantee seeds you collect and sow will be anything similar to
the
mother plant, in most cases probably not. This can be good if
you
want to see what you come up with, as breeders do in a controlled
fashion.
If you want to assure the same plant, you'll need to propagate it such
as by division. Sow seeds fresh, and even then they may take
several
months to germinate. Or you can hold in moist peat and keep
around
40F for 6 weeks prior to sowing.
*I have a Final Touch daylily which has never
bloomed. I have had it for 3-4 years. (Oklahoma)
Usually a daylily should bloom by the third year, even if from small
division. Possible causes for lack of bloom might be too
little light
(they really need full sun, or mostly full sun), too wet or too dry
stressing
the plant, or perhaps too much fertility (if the plant looks vigorous
and
green but wont bloom). If none of these fit, try different
culture,
or try stressing the plant a bit (less water, less fertility), and
sometimes
this may trigger bloom. Even moving to a different location
may help
sometimes.
*I have several coreopsis
plants.
Should I cut off the dead blossoms, and if so, where do I make the
cuts?
(New York)
You dont really need to cut off the past flowers of coreopsis, other
than for aesthetics. If so, and there are usually so many
flowers,
it is often easiest to just use grass shears to cut the plants below
the
flowers, leaving most the leaves on the stems.
*I've been picking tons of asiatic
garden beetles off my flowers. Is there anything I can do?
(Rhode
Island)
These beetles are chestnut brown and look similar to a Japanese beetle,
and have a similar life cycle, but don't skeletonize leaves rather
strip
them, often just leaving a midvein. If this is what you have,
you
likely have this beetle. They like moisture, so this year
with all
our rain we've seen many, even here in Vermont. They seem to
be mainly
in the northeastern U.S., are attracted to light, and feed at night
dropping
to the ground during the day. The grubs feed on turf, the
adults
feed on many flowers and vegetables during July and August.
Control
grubs in July through mid-September with approved pesticides, making
sure
to read and follow label directions. Keep in mind some
products may
also kill beneficial insects. Products for adult beetles may
also
be used with the same precautions. Few if any specific
biological
products are available. Of course handpicking may also work
if few
in number.
*Are the blue
lupines seen in June in fields
all over northern New Hampshire and Maine the native lupine perennis or
are they escaped non-native garden plants? Any good
suggestions for
blue native flowers we can plant? (New Hampshire)
The blue lupines are likely the native species, compared to hybrids
which are generally in other colors. Some other native blue
options
for the Northeast might be the blue lobelia (Lobelia
siphilitica),
Blue Stars (Amsonia), Blue false indigo (Baptisia),
New England
Aster, and Virginia Bluebells (Mertensia).
*I will be moving
from in September. I
have 3 favorite perennials including hosta and peony I would like to
take
with me. What is the best way to transport them. (Ohio)
Although spring is ideally the best time to move perennials, as growth
is starting (except peonies which are best moved in the fall), fall is
the next best time. The earlier in fall is best, to allow
plants
enough time to reestablish. Otherwise you may be better off
overwintering
in pots, in a cold but nonfreezing space. If you can't get
the plants
back in the ground within a couple days, it is often best to hold in
pots
of soil, even if temporarily before planting. Keep moist but
not
wet. Cut back top growth by half to 2/3 to balance the loss
of roots.
In the case of hostas and peonies, this would mean cutting off all top
growth.
*What kinds of plants can be planted along a
non-spring-fed pond
to help keep it clean? This is a large pond , over an acre, and I
understand
that cattails and other plants will help filter the pond water.
(Vermont)
You're correct, cattails are probably the best known water plant, along
with reeds and rushes, whose dense root systems absorb excess
nutrients.
Pickerel Rush helps scavenge decaying organic matter, reducing food
sources
for algae. Aquatic mint is quite aggressive, so is excellent
to keep
algae away. Taro is fast growing, absorbing excess nitrogen
and storing
it in edible tubers. Others that are effective at keeping
ponds clean
are Duck weed, Fairy moss, and Water hyacinth. Keep in mind
that
many such aquatic plants are considered invasive in many areas, and may
even be banned in some states. If using such
plants, make sure
your pond is contained and there is no way such plants can reach
waterways.
Many of these may also be hardy only in warm climates, so have to be
treated
as annuals in the north.
*As a bride to be I am drying
pink rose petals to use in my invitations. I'm pressing them
between
sheets of paper in a heavy book, but find they are losing their
colour.
Can you please offer me any advice as to how I can insure my next batch
of rose petals keep their lovely strong bright pink colour? (London, UK)
Commercial firms use expensive freeze drying to preserve roses and
other flowers so they look fresh. There are several methods
to dry
flowers such as roses at home. Keeping them out of the light
as you
did is a first step to preserving their color. The method you
used
of pressing and drying between sheets of paper, while keeping light
out,
often may not be best to preserve the color though. A more
recommended
method is to gently, but completely, immerse the flowers in a container
of the drying material silica gel, available at many craft
stores.
Or you may use various combinations of sand and borax and cornmeal,
such
as 1 cup sand, 2 cups borax or 1 cup borax, 1 cup cornmeal.
Just
watch for insects that might be attracted to the cornmeal.
You may
also try a layer of petals on a sheet in a warm oven. You may
also
try the microwave, in which case you should also put a cup of water in
with a few flowers at a time. Put flowers between paper
towels, use
low power, and only a minute or two at a time. Flowers may
lose color
and become brittle, however, in a microwave. Dehydrators, as
used
for vegetable slices, also are used by some. Some varieties,
in spite
of all this, just don't dry well and keep their color. I hope
yours
isn't one of these. good luck!
* Since my black-eyed susans began to grow this
spring, their tops
look as if someone came along with a sharp instrument and cut
them off. They grow again, and the same thing
occurs. What
is causing this problem? (New York)
Do you have deer nearby? They, or possibly other mammal such
as groundhogs, even rabbits (if not too high) can cause such
injury.
Late summer blooming perennials such as these may not be affected, IF
no
more injury, they just may bloom later. You may want to try
smell
repellents such as bars of soap hung nearby if deer, or taste
repellents
such as pepper sprays on the plants. If they are real hungry though,
only
fencing out will help. If plants don't bloom this year, they
should
come back fine again next year.
*I recently bought a Concord Grapespiderwort.
You mention in your article to cut back after bloom when the foliage
gets
ratty. Mine has reached the ratty stage and my question is
how far
back should I cut it? (Vermont)
You'll only need to cut back spiderwort (Tradescantia) if the foliage
becomes unsightly or infected with rust after bloom.
Otherwise, only
deadhead back to lateral buds which will then bloom. If
needing to
be cut back, do so by 2/3 or to the ground, as new growth will emerge
from
the base. It will be shorter, and bloom more sparsely. If
stressed
by heat or drought or such, it may not rebloom. Keeping the
soil
moist helps promote rebloom.
*Can I plant hostas
under a maple tree?
(Illinois)
Yes, in fact these are one of the best just choices. Just
make
sure and keep plants well-watered the first few months or year until
they
are established. Other choices might be vinca vine (if not
invasive
in your area) underneath, and daffodils between. Foamflower, barren
strawberry
(Waldsteinia), and dead nettle (Lamium)
are some other choices.
*I have a problem with earwigs
eating
my flowers, especially hollyhocks, zinnias, and roses in bud. How can I
control them safely, as I also have pets. (Colorado)
Earwigs are among our least favorite insects, but they do serve a
positive
function of eating aphids in the garden. If
you have a heavy infestation of aphids, this could be helping to
attract
the earwigs. Aphids can be treated with
insecticidal soap, devoured by lady bugs, or knocked down with a strong
spray of water from the garden hose. I would
not suggest washing them off in your case however, since earwigs like
moisture.
Earwigs tend to build up in an area with decaying organic matter combined with constant moisture. Watering regularly at night, a wet spell of weather, overly thick organic mulch, and decaying plant material can all make an area attractive to them. If you can make the area less attractive to the earwigs, they should decline in number. Fluff the mulch with a rake to help it dry out. Avoid daily sprinkling or light watering in dry weather, instead, water deeply less often. Next, you can try catching and trapping them. Although time consuming, hand picking at night by flashlight is best. Chemical controls are also possible. Check with your local garden center or Extension Service for locally approved ones. (answered by Nancy V.)
*Can I use horse
manure mixed with wood
shavings in the garden? (Vermont)
Using this fresh may rob the soil of nitrogen, as the microorganisms
breaking down the wood uses it up. One solution would be to
add 30-50%
more nitrogen to the garden. Or you can first compost the
manure
and wood mixture, adding more nitrogen there as well to aid proper
break
down. Beware any fresh manure products
for weed seeds.
Horse manure is usually pretty safe, if they have fed on weed-free
straw
or grass. Any manure from animals feeding on hay with weed
seeds
will add these seeds to your garden, unless it has been composted
properly
and at high temperatures.
*Books say to cut lavender
back in the
spring, but we live in a cold zone in Vermont and never do.
Should
we? (Vermont)
First, to survive in your USDA zone 3 climate (they are rated zone
5 at least), you must have good snow cover! If they survive
fine,
then no need to cut back. In marginal climates, they often
get straggly
by spring, so cutting back helps stimulate new growth and make more
uniform.
Cutting back in warmer climates does similar, and helps shape and keep
at a certain size.
*If I bring
primrose in to give as Christmas
presents, what do I tell people about their care? (Toronto)
Primrose, especially the English ones (vulgaris species and hybrids)
do make nice holiday presents as you suggest, potted in a good
houseplant
medium such as soilless mix. Just advise to keep them watered (don't
overwater)
and fertilized lightly after bloom. Yellowing leaves may indicate too
low
light, too cold, too hot, too wet, or hungry. Keep in a fair amount of
sun indoors, in as cool as possible, even unheated areas if they remain
above 40degrees F or so. Then plant outside in spring after
heavy
frosts are past.
*Can you suggest the best perennials for a seaside
garden in northern California, about 1 mile from the ocean on a high
peak.
There's nothing between my yard and the Pacific Ocean. It is
quite
windy and often damp throughout the summer due to heavy fog.
(California)
You might consider some of the many aloes and agaves and
fuchsias.
Other flowering perennials might include thrift (Armeria), Santa
Barbara
Daisy (Erigeron), Sea Holly (Eryngium), Sunrose (Helianthemum),
Daylily,
Coralbells, Candytuft (Iberis), Torch Lily (Kniphofia), and Perennial
Geranium
(Pelargonium). Some for foliage might include Blue Fescue,
Hosta,
and New Zealand Flax (Phormium).
*Do you have any tips for creating a winter
garden or caring
for a winter garden in Southern
Cal? (California)
Gardening and plants really depends on location in Southern California,
as there are many microclimates created by mountains, canyons, deserts,
and ocean. Areas near the coast remain mild and so adaptable
to a
wide range of most plants that don't require cold to bloom.
The exception
would be some canyons, such as near Laguna Beach and San Clemente that
can funnel cold winter winds, dropping temperatures near or below
freezing.
Hardier plants, and some winter protection might be needed in these
areas.
Other inland canyons might funnel the hot and drying fall and winter
Santa
Ana winds. Protect plants in these areas with windbreaks, row
covers,
and sprinklers. Some areas are transitional, with influences
both
from the ocean and inland, sometimes in the same day.
Temperatures
can vary widely in these areas, often providing enough heat for oranges
yet enough cold for many temperate perennials and shrubs such as some
lilacs
with less chilling periods to bloom.
Plants often found in Southern Calif. include many from the Mediterranean, Australia, South Africa and similar climates. Such a garden might include succulents such as Aloes and Agaves, with Protea family species such as Banksias, Grevilleas, Proteas, Leucospermums, and Leucodendrons. Other winter blooming perennials one might find say around Los Angeles might include Clivia, Iceland Poppy, Ice Plant, Mesembryanthemums, some Narcissus (those with minimal cooling requirement), and many South African bulbs.
*It's fall and I am moving
and want to
take my perennials with me to my new house, how do I do this without
harming
them? Do I plant them outside or in pots? (Indiana)
When moving perennials in the fall, get as many roots as possible,
cut the tops back to balance loss of roots, and keep roots
moist.
Best to move as soon in fall as possible. If moving
a short
distance, you can go on and plant. If moving over a longer
distance
or time, you can pot temporarily (this works in summer too if you can't
replant right away, or don't know when you can replant). Best
to
replant in the fall, and mulch well to help keep ground temperatures
warmer
and roots growing longer. You can hold in pots if a cool,
non-freezing
area with light-- just keep moist.
*How do I control the Japanese
beetles
that devoured my roses this past season? (answer provided by
Marilyn
W.)
Beetles appear in late-May. They often prefer to feed together in
masses
on flowers and foliage of plants leaving large round or irregularly
shaped
holes. They feed in the daytime and prefer bright sunlight, beginning
with
the top of the plant and working downward. Odor seems to be a very
important
factor in their food selection. Populations usually peak in June and
taper
off through July.
Early in the morning, before the beetles become active, pick off or knock off by hand into a can of water covered by a film of oil or kerosene. Be aware that many pesticide chemicals, while effective, may be toxic to beneficial insects, such as bees. Read all the instructions carefully, and follow all the precautions when using chemical treatments. Japanese beetle traps with pheromone lures to mass-trap them can actually make the problem worse, by attracting more than they kill, and so often are not recommended. Pesticides commonly used for lawn grub control will also control Japanese beetle grubs as will milky spore disease, although results are often erratic. Try interplanting with species that may actively repel the adults-- white mums, rue, tansy, larkspur, garlic, and citronella. Covering with floating row covers can protect prized roses and ripening fruit. Cut your roses as soon as them begin to open and take them inside to enjoy.
*My daffodils and amaryllis are softy and mushy, with
grubs eating
inside. I understand this is from the narcissus
bulb fly. What do I do for control?
As you probably already have seen, the grub or larvae of the bulb fly
destroys the insides of the bulb, and is difficult to control having
few
natural enemies. It will affect not only daffodils but many
other
bulbs. It comes from an egg, laid by a female fly in early
summer
that resembles a bumblee bee. Unlike bees though, these flies
have
a rapid flight, tend to hover, and are looking for dying bulb foliage
instead
of flowers. After mating the female lays eggs at the base of
dying
bulb foliage, the egg hatches and the larva tunnels down into the bulb
scales and then feeds its way into the bulb center destroying it. It
will
pupate in the spring, giving rising to yet more flies to start again.
An effective but time-consuming control is to watch for the bees and catch them with butterfly or insect nets, each one caught preventing 100 or so larvae. Or you can "hide" the old foliage from the egg-laying flies by dense groundcovers such as ajuga, pachysandra, or vinca. Instead, or while these are establishing, you may cover bulbs with lightweight ground cloth until midJuly. Planting bulbs in grassy areas, or among perennials which will hide dying foliage should also deter the flies. Cut off dead foliage immediately as it dies back in early summer, and cultivate around bulbs to hide the remaining bulb tops from the flies. Apply diatomaceous earth around bulbs every 10 days in late May and June to deter grubs. Pyrethrin or rotenone dusts have also been recommend where available and legal. An insecticide drench may also be applied in early May--check local stores for current products. If a few bulbs, they may be dug up and infected ones (soft, mushy) discarded making sure to kill the larvae. More tricky is a hot water bath, 110degree F for 30 minutes, but avoid much hotter as it may damage the bulb.
*What product or process can I use to keep squirrels
from digging up our bulbs after we plant them. (Wash.)
Often squirrels, skunks and other small animals are going for what
you plant with the bulbs if they smell bone meal. So use a
non-fragrant
source of phosphorus such as bulb food, rock phosphate, or
superphosphate.
If already doing this, try daffodils which most animals tend to leave
alone
compared to tulips which most like. If planting singly,
sprinkle
some crushed rocks or shells (you can buy them just for bulbs) in the
hole
after you place in the bulb. This deters digging noses and
paws.
If all else fails, over the bed with wire mesh such as chicken wire, or
make a cage buried in the ground to plant into. If local laws
permit,
you can also try trapping squirrels and chipmunks with the cage-type
traps
and relocating them.
* I have a large zone under
pine trees.
I would love to have a shade garden there but have heard that it is
difficult
to get anything but fern to grow in the shadow of pines. Do
you have
any suggestions? (Michigan)
This situation involved not just dry shade, but acidic soils as well
from the pine needles. Some plants I and others have found
success
with under coniferous evergreens such as pines include epimediums, wood
poppies, violets, columbines, european ginger, snake root, sweet
woodruff,
lamium, bishops weed (quite root invasive), yellow cordalis, bearberry,
bunchberry, blueberry, wintergreen, woodland anemone, coralbells,
bleeding
heart (eximia species and cultivars) and hosta.
* I just planted black
eyed susies
about two months ago. They were doing great, alot of blooms
and then
in a matter of two days, the leaves all turned brown and they are
dying.
Nothing else I have planted there has done this. What could
be the
problem. (New York)
Something this quick sounds like a bacterial blight, which may have
come with the plants, or invaded due to some insect damage or other
stress.
Most fungal diseases work slower. If blight, you should see
blackened
areas when you scrape the top layer off of the stem surface.
Something
disturbing the roots such as moles or chipmunks would result in slower
wilting first and eventual browning of leaves. If a blight,
digging
and discarding (not in compost) is the only solution
unfortunately.
I might also wait to replant something in that spot until next year,
and
preferably not the same plant for a couple years.
*I have about 1/4 acre of lawn invaded by the
perennial bugleweed.
I do not have this in my garden, but think it came in with bark
mulch.
What can I do to remove it permanently? (Vermont)
Short of scrapping the entire surface of the area, or removing it such
as with a sod cutter, putting new soil and grass seed down, you might
try
a herbicide if not philosophically adverse to such. The
"organic"
ones which are basically heavy salts and just burn foliage, wont really
get the roots. A broadleaf one (some of these may
persist in
the soil) will get any broadleaf plants and other weeds in your
grass.
A systemic one such as Roundup kills anything green, which if just
bugleweed
there and no grass, that may not be a problem. A small area
can be
covered with black plastic for a few months or year, and hopefully the
heat and lack of light will kill the plants. If you have this
or
similar plants in perennial gardens, make sure you keep them in the
beds
with proper edging!
*What are some organic
methods of controlling
insects and diseases on herbaceous garden plants? (New York state)
There are many controls that can be considered organic. One
is
to plant cultivars that are resistant to certain diseases, or that
repel
certain insects. You can use trap crops to lure the insects
away
from more valuable crops. Crop rotation helps to minimize
insects
and diseases, by not giving them time to get too well
established.
You can also remove insects by hand, or using certain devices to catch
them. There are also plant derived organic pesticides that
can be
used to control insects. You should never reuse soil where
diseased
plants have grown, or put diseased plants into your compost.
(answer
by C. Lynch as part of PSS course)
*Could you tell me whether deer eat
daisies.
I love daisys and recently moved near woods with a deer population.
(New
York)
Daisies (Shasta) are usually resistant to deer feeding, but if too
many deer or hungry enough, they will eat most plants. You
can find
more "resistant" perennials in my online leaflet
(http://www.uvm.edu/~pass/perry/oh64.html).
*I have a plant which was sold as "ghost
plant."
I have grown it in my garden and it has white plumes something like
astilbe
but it is about 5 feet tall. Can you tell me what I have and
whether
or not it will perform in dense or filtered shade? (Illinois)
That's the problem with common names, and why you should encourage
your nurseries to also list the scientific names! There are
several
plants called ghost plant, but most are desert or tropical or
such.
What you probably have is Artemisia lactiflora, often known more
commonly
as mugwort. There is a photo of a popular cultivar Guizho at
the
Blooms of Bressingham site
(http://www.bobna.com/products/artemisia_lactiflora.htm).
If this species is it, it should be hardy in your hardiness zone 5, but
isn't in our zone 4. It really needs full sun to grow best,
and may
be poor in shade. It needs well-drained yet moist soil as
well.
*I'd like a list of new
perennials for this
year, ones that need to be better known. (Pennsylvania) 5/03
This is one of the most fun to me, yet hardest items to keep up with,
as there are just so many-- many more than with annual flowers it
seems.
Many growers have their own introductions, and there are always new
ones
coming into the U.S. from abroad. First, visit your local
full line
garden center or specialty perennial nursery. Also visit such
online.
One national program, with retailers in most states, that introduces
new
plants from the UK is the Blooms of Bressingham program. You can also
check
out my monthly perennials from the homepage on this site to see new
selections
including perennial plants of the year, or existing but good and
underutilized
ones. Past selections can be found under the A-Z listing of
plants,
also from the homepage.
*I'd like to plant some heather,
do they
need full sun or will they take part shade? (New York)
Heather prefer full sun, but tolerate part shade, just don't bloom
as well in part shade. Other keys to their successful culture
(USDA
zones 4-7): don't overfertilize, plenty of water, acidic soil, very
well
drained soil, sandy soil is best. Give some winter protection
such
as evergreen boughs, to prevent drying in spring prior to new
growth.
If vigorous, cut back about half way in spring prior to new growth.
*I'd like to make some cuttings
of perennials,
how do I go about this? (Vermont)
There are several types of cuttings described, and some common plants
listed, in our leaflet
on Rooting Cuttings.
*Could you recommend some perennials for part shade,
under adrip
line of a roof? (New Hampshire)
Obviously you don't want tender stems that can get beaten down with
heavy rains. Some of the stronger, more upright ferns such as
Royal
and Cinnamon would be good for 3ft or so. Perhaps bergenia,
or some
hostas for lower heights-- just make sure you get upright selections of
the latter without the large tender leaves. For low groundcovers
consider
bearberry, vinca, or ajuga in cool climates, and additionally liriope
and
mondo grass in warm climates.
*What are some plants I can use to attract hummingbirds
to my garden? (Maine)
Some of the best perennials and biennials to attract hummingbirds
include
hollyhock, columbine, delphinium, foxglove, daylily, coral bells,
hosta,
blazing star, bee balm, and garden phlox. Some good annuals include
flowering
tobacco, scarlet runner bean, salvia, and even single
petunia. Whether
annual or perennial, avoid the double flowers as they are difficult for
hummingbirds and insects alike to pollinate. Choose a
selection to
provide color through the season, a succession of flowering times. For
more on how to choose flowers, and other important aspects for
hummingbird
habitats, see the leaflet on this topic. (http://pss.uvm.edu/ppp/pubs/oh76hum.htm)
*Is there such a thing as a perennial that will
flower throughout
the summer? Shady and sunny areas. (Kentucky)
As you probably know most perennials bloom on average 2 or 3
weeks.
I know of none that bloom continually in shade, although a couple that
may bloom for many weeks are the spotted deadnettle (Lamium) and
tuberous
begonia. In sun, some perennials including many shrub roses
(many
hybrids such as tea roses bloom pretty much continually) may either
rebloom
later in the season (other examples are some perennial salvia and some
perennial geraniums), or more often depending on plant and
location.
Your best bet is to pick a selection of various cultivars of a plant to
get a succession of blooms. This is particularly true for
such large
genera as daylilies and geraniums, which for me provide blooms from
June
through September, and May through August respectively.
*I have some small perennials in pots in a hobby
greenhouse. How should I treat them so they will get cold and
bloom
next season? (Toronto)
It sounds like your perennials are protected in the greenhouse, at
warmer temperatures? I would decrease the temperature maybe
5-10C
(10-20F) a week until it is about 5C (40F) or a little lower.
It
doesnt sound like the plants are large enough, or established enough to
take much freezing, hence keeping them about this. That
should give
them some cold, which hopefully will help blooms. Perennials
all
vary, some need cold, others dont, and some vary in the amount from 4
to
12 weeks. It is the longer days in spring that gets them
growing
again, so the sooner in fall you can give them cool temperatures the
better,
so sufficient time if they need cold, before spring. I would
still
keep them fairly cool even when they start growing, otherwise they
might
grow too fast, bloom, or get too leggy before you can put them out
safely.
*How do I improve heavy clay
soil?
(Delaware)
The best way is by adding organic matter (not sand), and lots of
it!
This could be shredded leaves and grass clipping from your yard or
local
recycle/landfill center, compost, peat moss or similar. This
may
need doing each year for several years. Of course a quicker
approach
is to dig it out and replace the soil, but this may be more
expensive.
More tips can be found at our garden leaflet on Gardening
on Clay.
*My daylilies haveorange
spots on the
undersides of leaves and plants don't look good. What should
I do?
(various)
This is most likely a new disease, found now in at least 20 states
and Costa Rica, a fungal rust called what else, daylily rust! (Puccinia
hemerocallidis) This is an Asian species, imported and first
seen on
plants in Georgia in 2000. It can merely cause the
characteristic
raised rust colored spots on leaf undersides to killing foliage. Some
cultivars
appear more susceptible than others, with Pardon Me one of the most
susceptible.
Happy Returns, Stella D'Oro, and Joan Senior are popular moderately
susceptible
cultivars. Holy Spirit appears among a few others least
susceptible.
Best control is by not introducing it, so if ordering daylilies or
buying
them in, some keep them isolated from others for up to 6 months or a
season
in the north to see if disease develops. If present, cut off
infected
foliage. Several fungicides for rust appear to control it,
but should
be rotated among different types every few sprays to prevent
resistance.
There are many websites on this disease, merely type daylily rust into
your favorite search engine.
*This past year all my lily plants
were devoured, buds, leaves even stems. What caused
this? (New
Hampshire)
If you see a fire engine red beetle with black head and legs, it is
the lily leaf beetle (Lilioceris lilii).
Similar in size to
the ladybug, it is slender instead of rounded. This is a new
pest
from Europe, first reported in Cambridge, MA in 1992 and now ten years
later throughout various parts of New England, especially the eastern
half.
Not only the adult beetles do damage, but perhaps more is done by
larval
feeding, these ugly insects resembling slugs and carrying their
excrement
on their back to deter predators! They feed on members of the lily
family
including hosta and solomon's seal. They don't apparently
feed on
the lily cultivar 'Black Beauty' though, nor daylilies which of course
are not true lilies. Control in spring by looking for and
removing
the lines of orange eggs on undersides of lily leaves. Adults
can
be handpicked if not many. Otherwise pesticides that kill
beetles
can be used, ones contained the plant extract Neem being least toxic to
other organisms. Although easy to control, new ones
continually fly
in, so spray weekly if needed.
*Does the last
time I can
plant perennials depend on how hardy they are? (Vermont)
The last date perennials can be planted in the fall depends not so
much on how hardy but rather on size of plant and soil type, and of
course
location. Young, small, poorly rooted plants may not have
sufficient
vigor and root and crown mass to take low temperatures, but in more
mild
areas they may establish fine. In cold areas experiencing
frost heaving
especially in the Spring, plants should be well-rooted so they dont
heave
out of the ground as readily. This may be more in clay than
sandy
soils. A couple points to keep in mind on rooting: perennials
may
need about 6 weeks (depending on soil temperatures of course) to
establish
some roots. And roots generally grow about about 40degrees
F.
In USDA zone 4, this may be until about first of November on
average.
So for instance in USDA zone 4, mid September would be a good last date
to plant. Of course it could be later as noted above if large
plants
and good soil with little chance of frost heaving, perhaps even until
the
ground freezes.
*Local home improvement centers
are now
selling their perennials at half price (late fall)--is this a good
bargin
for zone 5? (Pennsylvania)
It depends. You often get what you pay for with plants
especially,
so beware. If you don't expect a lot from your plants, and
are willing
to put up with some losses, you may not be disappointed with
bargains.
Many perennials are fairly tough, so it depends on what the plants are
in part. Also for a fairly cold zone compared to many in the
country,
just make sure the plants are hardy and truly perennial in your
zone.
Look for information on the tags, or ask the sales staff.
Often with
big chains, the buying is done elsewhere and the same plants shipped to
all stores, so some may not be hardy. And of course look for
good
growth, vigor, and lack of pests or disease problems. Some
big chains
provide minimal if any maintenance of their plants, including
watering.
Effects of such stresses may not be apparent now (unless plants are
wilted
of course), but may show up the following year with poor growth or even
no survival. So if you do get such plants, and they don't
perform
well, don't necessarily blame yourself for not knowing how to care for
them!
*We would like to sow seeds from a hosta,
and don't know how, or what the seeds are. Please
advise. (Vermont)
Hosta seeds are ripe when the pods turn brown and begin to
split.
If your season is too short for this, bring pods indoors and place
stems
in a floral preservative as you would for cut flowers, changing it
periodically.
Place brown pods in paper bags to allow to split and discharge seeds,
or
if not, use tweezers or similar to remove seeds from the pods, blowing
off any husks. Seeds often germinate easily if sown fresh,
otherwise
store as you would other seeds cool (40F) and dry. If not
sown fresh,
to germinate you may need to then sow in a moist medium, and keep cool
(40F) for about 3 months. Keep in mind seedlings are often
quite
variable from the parent(s). The seedlings are
often quite
variable due to crossing with other nearby hostas. Even if
all parents
are the same, or only one plant, there still is sometimes
variability.
It often takes 2 years to get plants to show their true traits, in
order
to cull out ones not like the parent plant, and often 3 years to bloom
from seed.
*I have purple siberian iris, with what appear to
be seedpods
and layers of seeds inside. Is this correct, and will this
take away
from next year's blooms? (New York)
It does sound like the seeds, and these plants are generally pretty
tough, so it shouldnt take away from next year. If you have
others
nearby, they may cross and come up with other seedlings.
Otherwise,
left on their own, they may self seed themselves, sometimes quite
prolifically.
*I have 'Jacob
Cline' bee balm and I would like
to propagate them. What is the best way? (Pennsylvania)
As with most monardas or bee balms, root cuttings most times of the
year are successful, or divisions as plants emerge in spring, or
cuttings
of new growth. Easiest are root cuttings, with pieces of root
laid
in a moist medium such as potting soil, or half vermiculite and
perlite.
Don't keep too wet. Also easy is dividing off pieces of the
main
plant in spring, with several shoots per division.
*I can't seen to grow Black
Eyed Susan
in my yard - as soon as new sprouts come up they are eaten.
Any advice?
(Connecticut)
It sounds like you might have rabbits? or groundhogs? Usually
deer eat off plants higher. Have you noticed any?
Check out
my leaflet on animals pests (http://pss.uvm.edu/ppp/pubs/oh52anml.htm)
for more ideas on these, and other possible predators.
*Will bulbs grow up through a layer of
mulch,
or do I have to open up space for them? (Vermont)
Yes, if an organic mulch and not a solid plastic covering
material.
Use only a couple inches, which will in addition to helping conserve
moisture
and prevent some weeds, also help moderate soil temperatures in spring
and fall. In northern climates such as Vermont, the increased
soil
temperatures from only a couple inches of bark mulch may extend the
rooting
season for bulbs two or more weeks which is often quite beneficial.
*Canannuals
and tender perennials be overwintered
indoors? (Vermont)
It depends on the annual, and indoor conditions, but many can if
sufficient
light and temperatures between 50 and 70 degrees F. Or they
may last
through fall, giving some color indoors. Just treat as a
houseplant,
fertilize according to label directions if growing and blooming, and
watch
for pests. Coleus dianthus, and geraniums in particular are
often
overwintered indoors. Tender perennials that we grow as
annuals in
the north, like many salvias, can also be held indoors if
cool. Too
much heat, with too little light, for any of these may make them
spindly
with little or no bloom.
*Why do petals of my black-eyed
susies
won't open up? The flowers look so wierd. They have large dark center
but
the yellow flower petals are like pointed needles. (Toronto)
There could be several causes, but most likely either drought, or
insect
damage. Often insects feeding in early flower stages, before
buds
even open, cause strange and distorted flowers. Unfortunately
the
damage was done a while back if from insect feeding, so too late to
control.
But the good news is the plants should be fine next year, just watch
for
insects when you start to see buds. This applies to other
flowers
as well with such symptoms.
*Our Elijah
Blue fescue has gone to
seed. Do we need to remove the brown seed stems or leave them on?
(Wyoming)
Leaving seed stems on grasses, including this one, is usually just
an aesthetic consideration. Often they can be quite
attractive in
fall and winter, especially on the taller grasses. On this grass, if
you
just want the bluish effect, you may want to remove them. The only time
you would definately want to remove them is for seed invasive grasses
such
as some Miscanthus in warm climates (often they don't set seed in
shorter
and cooler seasons in the north).
*I found large grubs
in bearded iris rhizomes
when dividing them in late July. What are they? (Vermont)
Iris borers. Eggs are laid in the fall near the basal leaves
and hatch in April. The larvae eat their way down, inside the leaf,
until
they reach the rhizomes. They then grow to 1-2 inches long with a soft,
fat, pink body with a brown head. Not only can the larvae eat
rhizomes,
but more damaging can be the bacterial soft rot which enters the
wounds.
This often has a foul smelling odor. Larvae then enter the soil in late
summer, pupate, fly around as moths in early fall and lay eggs for next
year.
Chemical controls prior to
bloom may be effective,
but best control is prevention. Remove any diseased foliage
in the
fall. Monitor in spring for small holes in the lower leaves
where
larvae enter and feed on their way to the rhizomes. Then if
signs
of fairly quick dieback and poor vigor after bloom, check rhizomes for
rot and cavities where the larvae feed before entering the
soil.
Destroy affected rhizomes, and larvae (wire in their cavities works
well),
and sanitize with one part bleach to 9 parts water before
replanting.
Check soil too for any larvae.
*I would like to know some good, environmentally
friendly ways toclear
out large grassy areas (acres)
to replace with wild flower seeds. (Massachusetts)
The first thing to realize is that to have success with wildflowers
over the long term, you'll need a good mix with many native perennial
varieties.
And you need an excellent seedbed, and care, as if you were seeding a
lawn.
This can be difficult on large areas. Of course some use weed
whacking
and mowing to lower grass levels, then kill it with roundup.
More
ecological though is to lower grass levels as above, till thoroughly,
then
cover crop for several years prior in order to reduce weed
populations.
If a smaller area, you may wish to cover it with black plastic for at
least
a year after lowering grass levels, then remove and prepare
the fine
seedbed. Even with all this, more competitive weed seeds from
surrounding
areas may blow in, and become established after a couple years, so
reducing
these populations if possible will also help.
*Are antidessicants
effective?
(New York)
Yes and no. Antidessicants supposedly prevent dessication, or
drying out, of foliage. Many resemble latex type compounds,
putting
a film on leaves. Over time this may wear off, and of course
wouldnt
be on new growth appearring after application. Results for
use over
winter to prevent water loss from evergreen plants are mixed.
Often
the spray needs to get under leaves where water is lost, as well as on
top, and this may be difficult. They generally though are
effective
sprayed on plants, especially evergreens, after transplanting to
prevent
excess water loss to help balance the loss of roots.
*What are some groundcover herbaceous perennials that
would be salt
tolerant? (Vermont)
For salt tolerance of
trees and
shrubs, consult UVM OH leaflet 56,
http://ctr.uvm.edu/ctr/oh/oh56.htm
Some herbaceous
perennial groundcover
choices here would be bearberry, blue lyme grass, and
wormwood. Many
can be massed for a groundcover effect, including low catmints and
salvias,
blue fescue grass, sea thrift, some Allwood dianthus (such as 'Helen'),
some daylilies such as 'Stella de Oro', sea lavender, sedum 'Autumn
Joy',
and for warmer climates lilyturf.
*I need suggestions for Zone 5 groundcovers that will
provide weed
and erosion control on a slope
in full sun. The
soil has a mostly clay content and surrounds a pond. (upstate New York)
Slopes are a question I often get, and it seems a difficult situation
to deal with. There are several options, depending on your
needs
and budget. You might terrace the slope, either with timbers
into
more formal levels, or place boulders either at random or more in
organized
bed fashion. This will control erosion, and the terraces or
levels
can be treated as other flat areas either with grass or flowers or
such.
Otherwise, Id suggest sowing a conservation grass mix. This
will
have some weedy grasses usually, so is not best for formal
lawns.
Into this you can plant perennials such as daylilies, many perennial
geraniums,
catmints, ajuga (more for shade), lady's mantle, bee balm, coneflowers,
rudbeckia and ornamental grasses. These will eventually grow
and
shade out grasses, and provide seasonal color. You may also
wish
to add shrubs such as junipers or Russian cypress (Microbiota), which
will
eventually fill in too. There are many junipers from low
spreaders
to taller spreaders. Many of the shrub roses are good in mass
too,
especially the rugosa ones. You might even use more root
invasive
plants, such as the Blue Lyme grass or Ribbon grass, as long as there
is
no chance they'll wash downstream in a waterway to spread to other
areas.
*I have a problem with neighborhood
cats using
my tulip beds for litter boxes and destroying bulbs with
digging.
How can I prevent this? I do not know the pet owners.
(Michigan)
I have this same problem with my cat in my beds before the bulbs
emerge,
or in empty spots in beds, especially where I have a nice
topdressing
of compost. I would think once plants emerge, this should
deter them.
If not, there are some repellents you may find in garden stores to
spray
around. Or perhaps just rough material like course gravel or
shells,
even egg shells, may work. If bulbs arent up, you may cover
beds
with a fine metal mesh and remove it when bulbs appear. This
also
helps prevent damage from mice, voles and such. A courser
mesh wire,
like chicken wire, may be used before bulbs emerge, and also may allow
them to come up between the wire and so be left on the bed.
Obviously
a small fence around the area (but high enough so the cats wont jump
over),
may be a possibility as well in some situtations.
* I received a potted
tulip as a gift.
Is there a way to have the bulb bloom again, what is the procedure?
(Mexico)
It is difficult to get bulbs forced in this way to bloom
again.
It often may take a couple years, and tulips even planted out in the
garden
often are treated as annuals. If you want to try, you can
keep watered
and growing until the foliage dies off, perhaps in summer.
You can
leave in the pot, then in the fall give at least 12 weeks of cool, in
moist
not wet soil, at refrigerator temperature, about 40F. Water
with
some liquid fertilizer then too. Then bring back into the
warmth.
The bulb may grow, but not bloom well if at all. Then repeat
another
year, perhaps it will bloom better the second year.
*I am trying to grow rugosa
roses from
seed. Didn't work last year. Any suggestions?
Perhaps if these were seeds you collected yourself, they were not
viable
to begin with? Or maybe they needed different storage (cool
40degrees
F, dry is often best for seeds). Or perhaps they needed
different
germination conditions. Most rugosa roses spread more by
roots, and
root fairly easily by cuttings, so if seeds still don't work these
might
be options. Keep in mind those from seeds may cross and yield
flowers
unlike the plants you got them from, if a particular color was of
interest.
Try again, picking when just ripe, not soft, immediately removing the
surrounding
fleshy coat, then place in moist sand or peat at 40F for 6 months prior
to sowing..
*With all this warm
weather this fall, my
perennials are starting to sprout and green up. Should I
mulch them,
or leave alone? (New York)
I'd mulch for a couple reasons. It will protect the new
growth
if tender, and it will help prevent ground temperatures from getting so
warm on sunny days thus stimulating plant growth. It can also
prevent
temperatures from fluctuating so much. Even an inch or two of
bark
mulch can keep the soil 5 to 10 degrees warmer on a cold day than
uncovered
soil, or cooler than open soil on a hot day. I'd also use
some weed-free
straw, or leaves that don't mat down (maple for instance) around the
new
growth.
*I had a very unpleasant encounter with a euphorbia
this summer,
and I'm still bearing scars from the awful blisters. Please
send
me information about the toxicity
of euphorbias,
as no big deal is made in most books. They just explain that
it is
a skin irritant. I had to go to a physician's office! (Vermont)
Yes, this is what most references will list for such skin irritants,
the degree varying with the individual and the species of
plant.
(I personally have no reaction from Euphorbias yet have heard of such a
case as yours before.) If you learn from such experiences, or don't
know,
that you are susceptible to such irritants, treat all with
caution.
Make a list of all the plants in your garden, checking them against
references.
If you don't know a plant, treat it with caution until proven
safe!
One place you may wish to start is my leaflet
on Potentially Harmful Perennials.
*I want to find a list of perennials suitable
for containers.
(Germany)
You'll find cultural
summary, and lists
of species in new leaflets on this site. Choose plants that
will grow
in proportion to the container, both in girth and height.
Plants
should fill out the pot during the season, and be no more than 2 to 3
times
as high as the container. If plants are too small for a
container,
they wont fill it during the growing season, so may stay too
wet.
If too short, they'll look add, and if too tall may need staking or be
top heavy and blow over. If they fit these size requirements,
many
perennials may be used in containers.
*I was given a peony by someone who only
had a blood
red peony in her garden. When I planted it, the color was
light pink
to fuchsia. Is there anything I can do to get this color?
(New Jersey)
Probably not, except try another division or purchase one. It
sounds like perhaps the plant mutated as a result of some stress,
perhaps
division. There is nothing you can add like with hydrangea to
change
the flower color. I'd leave this one though and be patient,
perhaps
in another year it may revert back?
*I'd like to
know when a plant is done blooming
for the year, like a lily ....can you cut it down or should you leave
it
till it dies off ? (Wisconsin)
If separate flower stalks, like on daylilies or daffodils, you can
cut these off (leaving doesnt hurt either). If same stalk as
leaves,
as with many lilies, leave until stalk begins to die down--this way
food
reserves can still be made and sent to the roots while the plants is
living
and growing.
*Three years
ago I was given a well established
peony dug up from a friends garden. Last year was the first
time
it bloomed for me - this year, only one flower - the plant is very
lush,
dark green and about 3' accross by 3.5' high (no sign of
disease).
I give it a light organic fertilizer once a year and lime it at least
once
a year. It gets about 4.5 hrs of direct sun during the middle of the
day
- what can I do to improve bloom on this peony? (Vermont)
It sounds like you might need more sun if possible, or move it this
fall. Also make sure the crown with the buds from where the
stems
arise is only 1-2 inches deep. Too deep and peonies often
don't bloom.
Often bloom on perennials, especially early-season ones such as the
peony,
is determined by what happened last year. But with a moist
season
in our area last year, most perennials are performing quite well so far
this year and in fact many are loaded with buds and flowers.
So this
doesn't sound like a factor here with your peony, but something to keep
in mind for the future.
*What is
your favorite perennial? (Iowa)
You've probably heard all the reasons one can't pick a "favorite"
plant.
It's like picking a favorite child--they all have their good and bad
points.
Or, it's the plant I see at a particular moment! But one of
the many
I like, and feel underutilized is the Helenium. It
provides a mass
of daisy-type flowers in mid summer to early fall depending on location
(early in the south and UK, later in northern U.S.), 4-5 ft high and
across
(in moist years, as it likes moisture) of reds, oranges, yellows
(depending
obviously on cultivar). A drawback is that this heavy mass
often
needs staking, but there are some shorter ones like Coppelia that
dont.
Cutting back early, especially more so in the South, may keep plants
shorter
and avoid the need for staking. It's been popular, and bred,
in the
UK and Europe (particularly Germany) for years and only now are a few
more
finding their way back home (most species are native to the
U.S.).
I prefer the common name of Helen's flower (named after Helen of Troy,
and reminds me of my mother of this name), to Sneezeweed. The
latter
is such a misnomer, and probably reason it is not more popular here,
with
the ragweed which blooms at the same time causing allergies and not
this
one which people tend to notice and so think of as the culprit!
*There is a dense
shade area by a corner
of the house with no sun. Hard to find something to grow
here.
Hostas and hydrangea do OK. I would like something else, but
have
had no luck. Could it be the soil? (Ohio)
It is probably the dense shade and not the soil making it difficult
to grow plants there. Hostas are good for this, but watch for
slugs.
Other choices for dense shade include ferns, barrenwort (Epimedium),
astilbe, ginger (Asarum), deadnettle (Lamium),
lily of the
valley, lilyturf (Liriope, warm climates), spurge (Pachysandra),
lungwort (Pulmonaria), foamflower (Tiarella),
vinca, viola
and barren strawberry (Waldsteinia). For
dry shade try hostas,
epimediums, deadnettle, vinca, foamflower, viola and barren strawberry.
* "Something"
ate my Solomon Seals.
A rabbit? Bugs? Creepy crawlies? What can I do? (Ohio)
Has your Solomon Seal resprouted? If not, dig around the
roots
to see if still there, perhaps with buds, or just mushy and
rotting.
Many perennials with this kind of damage early in the season will
eventually
resprout, or if late in the season resprout next year, so be
patient.
Usually you see insects chewing on leaves. If they have
holes, and
in such damp shade, it could be slugs. If they disappear
overnight
like this, could be a larger mammal as you suggest like a
rabbit.
See my leaflet on these pests and controls at
http://pss.uvm.edu/ppp/pubs/OH52anml.htm
*Two articles
from two different Extension Service
offices state that most perennials do well in pH of 6.6 -7.0.
Another
states they generally do best in 5.5-6.5. Can you put this issue to
rest?
This is often the kind of contradicting or different results that you
may find in references. Actually in this case with pH or soil
acidity,
both are right. Perennials are not very fussy in general
about pH,
a range of 5.5 to 7.5 being acceptable for most. Of course
some such
as heaths and heathers "prefer" one lower than this, and some such as
delphiniums,
dianthus, baby's breath, lavender and clematis "prefer" the upper end
of
this range. But the word "prefer" is key (and not one usually
seen
in references) as many plants grow outside their range of
preferences.
Milkweed (Asclepias) is one that may have problems above 6.5, and many
silver-leaved perennials prefer neutral to alkaline pH.
Rather than
focus on pH, if within this range, make sure plants have good organic
matter.
This helps "buffer" or resist swings in nutrition and pH. And make sure
for most, that they have good watering in summer, and good drainage in
winter.
*We recently
had a devastating hail storm which
destroyed all of our plants. What is the best way to care for plants
which
have been beaten down is such a manor? Should I cut them back? If so
how
much? (North Dakota)
First, my condolences for your storm and plant loss. I had
one
of these a few years ago, ripping my hosta leaves if not putting holes
all in them. With plants such as this or peonies that only
grow once
in the season, cut off any parts that are definately broken and will
only
die. Rest, even though unsightly, can be left--just watch for
signs
of disease, and cut these parts off. For other perennials
(most)
that might regrow, rebranch or recover, cut off the broken stems which
again will only die. If the plant tends to branch, cut back
to the
leaf nodes (where leaves join stems) where new branches will come
out.
Some such as many perennial geraniums and perennial salvia can be cut
back
to either new basal growth, or to within a few inches of the ground if
early in the season, and new shoots should emerge. Some such
as daylilies
and iris, which are normally cut back to with 6 to 12 inches of the
ground
when divided, can be cut back to this. They may not grow much
this
season, but the foliage will help build stronger roots for the
following
year.
*I wanted to
know if I have to cut back my Purple
Allium flowers? They are huge, and I don't want to cut off
the tops
if I am not supposed to. (Utah)
You are probably talking of the giant Allium (or globe allium), an
onion relative. All members of this family you can cut the
flowers
off after bloom, and in fact with many you want to in order to keep
them
from reseeding prolifically. Just leave foliage to continue
growth.
You can even keep the narrow foliage of some cut back (as with chives)
as they regrow from the base.
*I have a retaining
wall with springs
keeping the soil damp in front of the wall. What are some good choices
for a shady, moist soil ground cover? I have had luck with
ferns.
(New York)
There are so many ferns to choose from, you could have a variety of
heights, foliage colors and textures just of these. Other
choices
might include primroses, astilbe, turtlehead (Chelone),
barrenwort
(Epimedium), globeflower (Trollius),
marsh marigold (Caltha),
even lowbush blueberry (Vaccinium). There
are many taller
perennials as well for moist shade, including bugbane (Cimicifuga)
and Helen's flower (Helenium). If root
invasive plants aren't
an issue at your site, you might even consider the loosestrifes (Lysimachia)
or variegated ribbon grass (Phalaris).
*My
primrose leaves are very limp and falling
off, some have black leaves. Doesnt look like it needs water. It has
fertilizer
and food. What's wrong? (Alaska)
If a plant like this has wilted leaves, yet plenty of water in the
soil, it could mean that water isn't reaching the leaves due to a root
disease such as from fungi, or stem disease such as from
bacteria.
If the latter, not much you can do except toss the plant.
Check the
roots though, and if the former, some should be mushy or discolored or
darker than the usual white roots of most plants. Remove the
diseased
roots, repot or replant the plant and keep on the dry side.
Hopefully
new roots will form, and the plant will recover. There are
some fungicides
for root rots, but often they are specific for the disease with not one
chemical covering all. Check with your local university
Extension
plant diagnostic lab, if one, or local Extension office, to see how to
get this disease identified if the cultural treatments above don't
work.
*Myholly
hock leaves are turning brown and
withering. There is enough rain so dryness is not the
problem. what
can I do to save them?
It could either be a leaf disease, or
other disease to
stems or roots (this could include other damage) that doesnt let water
get from roots to leaves. Most likely it is rust disease--you
should
see rusty spots on leaf undersides (yellow on top) that eventually
causes
them to yellow, wither and fall off, starting with lower ones first.
Remove
first infected leaves you see at beginning of the season. There are
chemical
sprays you can use, as well as some organic ones such as sulfur, but
check
with your local garden center. Control often means frequent
reapplications.
Usually mine get this, but still flower fine. It is a common
disease,
and takes a lot of effort to control. Cut back infected parts after
bloom
and keep destroying any plant parts that get more rust, as it may
overwinter
on these.
*What is the
provincial flower of Nunavut--
the new Canadian Province? (Ontario)
The arctic poppy (Papaver nudicaule) was proposed as
the official
flower at the 1998 Ottawa Tulip Festival. Nunavut is basically the
eastern
half of the former Northwest Territories, with mainly an Inuit
population,
and came into existence April 1, 1999. Actually Nunavut is
not officially
a province, rather a territory, as are Yukon and Northwest
Territories.
There are still 10 Canadian provinces.
* What would be
a good perennial groundcover for
wet soil and sunny? (Ohio)
Is it a contained site--not near streams or
waterways?
If so, there are some root-aggressive groundcovers like the Polygonums,
Loosestrifes (Lysimachia) and mints, but if near
water roots can
spread downstream making them invasive. Vaccinium or lowbush
blueberry
might be a good choice if a more woody perennial is desired.
Osmunda
ferns and Siberian Iris are more tall and clumping, but placed close
they
provide a nice mass to cover the ground.
*What
makes 'Blue Fortune' Anise Hyssop
(Agastache) better than other cultivars?
This new cultivar from Rotterdam, Holland is a cross between two
species.
It has the abundant purplish-blue flower spikes, 3 ft height, and long
mid-summer bloom of its foeniculum parent (US
native), and the hardiness
at least to USDA zone 4 of its rugosa parent (Asian
native)--so
truly the best of both worlds!
*Before
my lilies
bloomed the leaves and buds turned brown. They bloomed, but not well.
Why?
(Virginia)
Probably drought. This is the main cause of such symptoms--too little
water. If too wet and soggy soil, leaves and buds often just fall off
and
turn mushy brown, as they do from disease.
*What
effect will this year's drought
(second worst in East on record) have on my perennials? (several states)
Obviously for perennials just beginning to bloom, or not yet bloomed,
they may not, or do so poorly, or bloom for a shorter period, or a
combination.
Perennials that bloom the first part of the summer set buds the
following
year, so the drought effects now will be seen on them next summer-- so
expect such symptoms of poor bloom, including fewer flowers, next year
on such as peonies, yarrow, spring flowers, and many daylilies and
lilies.
*What
are some perennials I can
plant that will take drought like we've been having this year?
(Massachusetts)
Some good candidates for dry shade include hostas, ajuga, vinca and
foamflowers. For sun try tickseed or coreopsis, coneflower, sedum (low
versions for rock gardens, tall ones such as 'Autumn Joy' for borders),
and Black-eyed Susan (Rudbeckia). Of course the
first few weeks,
or season, when planted these should be kept well-watered until they
become
established--then they can take the drought.
*I have
sandy soil, so my lawn and perennials
have not fared well this year with the drought. What's the best
solution?
(Massachusetts, New Jersey)
You're right, sandy soils do not hold much water. Plants this past
season in the East in clay or loamy soils have fared much better. So,
short
of installing plants that take the drought (see other question), or
installing
an irrigation system, you can begin improving the soil with organic
matter.
Small particle organic substances such as shredded leaves, sphagnum
peat
moss, or compost can be top-dressed (applied around) existing plants or
worked into new beds. Be sure and use plenty--several inches a year for
several years for really sandy soils (just be sure and don't bury
existing
plants!).
*What can I
expect from my Baptisia plant
the first year (it didn't bloom), and how do I prepare it for winter?
(Masschusetts)
Hopefully you planted it where you want it, as Baptisia grow large
(4 feet high and 6 feet wide) and resent moving. Keep it, as with most
perennials, fertilized and well watered the first year. Like most
perennials,
it wont bloom the first year as yours apparently didn't (the pea-like
flowers
appear in June). After tops die back in late fall you can cut them off,
or leave them until next spring. When plants bloom, they produce
attractive
black seed pods that make a nice rattle in the wind. This is a nice
effect
into winter, although leaving seedpods on fosters seedlings to be
weeded
the following year--so your choice! They are generally quite hardy.
*Should I
cut back perennials in the fall?
Yes, definately if they have disease and be sure to not put the
diseased
plant parts in compost unless you can ensure the pile will get to 140
degrees
F to kill the disease organisms. Otherwise, it kind of depends on your
time available and desire. Obviously you will want to wait until after
fall bloomers are through, such as Helenium and fall asters. If cutting
back, leave at least a few inches of stem to help trap snow and provide
some protection. Also, cut back as late as possible, in order to allow
nutrients from the leaves and stems to cycle back to the roots--
perhaps
late October in the north, late November in the south. On the other
hand,
I usually don't get around to it and cut back in the spring, and the
plants
are fine.
*How late
can I plant perennials and bulbs?
(several states including Alabama and New York)
Roots generally grow to about 40 degrees F soil temperature. This may
occur in open soil about Nov. 1 in the far north and Dec. 1 in the
upper
south. And you want to allow ideally about 4-6 weeks for roots to grow
and the plants to establish in the fall. Therefore early Oct in the
north
and early Nov. in the south are about as late as you should plan to
plant
out. Of course if you can't or don't get to it, you still may have luck
planting later, but it is more risky. Earlier planting and more
established
plants, especially if small, provides more winter protection and less
frost
heaving in spring.
*Why
didn't my tulips bloom this past
spring? (Oklahoma)
There could be many causes such as wet soil, poor nutrition especially
in previous years, shade, rodents, late cold killing buds. For those in
the north, the season may be too short for bulbs to store sufficient
food
for good bloom the following year before heat comes and kills the tops
back. In general, unlike some other bulbs like daffodils, tulips may be
less vigorous in future years and may only bloom for 2-3 years. I and
many
others generally treat them as an annual, replanting yearly.
*Where can
I find whether plant ??? is hardy
in my area?
Start by checking at your local garden center or nursery. Also check
on my links page, general category, for one of the plant search engines
such as the one from Time Life. Type in your hardiness zone, or the
plant
name. Don't know your zone? Check another site at same general category
for an interactive map for the U.S. There is another site with a map
for
Canada.
*Is
there a discussion list for perennials?
Yes. There are also ones for alpines and plant propagation among
others.
ALWAYS send mail to majordomo@mallorn.com! Your message should contain
the following two words of text:
subscribe perennials
don't forget to turn off your signature on your email if you have one.
*I
didn't cut
my perennials back in the fall. Is spring okay? (Ohio gardener)
Yes. I usually don't get around to mine, or am tired of gardening by
then, or want to see the winter effect of many perennials, and also the
stems helps trap snow for winter protection. The only time I usually
cut
back in fall is for damaged or diseased stems. Spring, just before
growth
(late April for us in USDA zone 4, week earlier for each zone further
south)is
when we cut back to about 6 inches above the ground. Then is a good
time
to check labels and relabel if needed.
*I
am new to the area (any area,
I've gotten this question from Alabama, Arkansas and Massachusetts
among
others) and want to know what to plant, what will grow well, and some
designs.
This will vary so much with region, but in general good in most are
peonies in early summer, daylilies in mid summer, hostas and coral
bells
for foliage and shade, and garden phlox and bee balm for late summer.
There
are many good sources of culture information on the internet-- check
out
my consumer leaflets page. For lists for specific requirements, check
out
the plant search engines and encyclopedias under General on my links
page.
For design, there's not much yet I've found on the net (let me know if
you know of some sites) but there are many good books-- check your
local
bookstore, also book companies on the net such as on my links page
(Timber
Press in particular specializes in horticultural books.)
*When
is the New England Flower
Show? (Vermont)
Check out their site at http://www.masshort.org/fsfs.htm.
Check out the "Virtual Boston" map, found through your favorite search
engine, for directions. Also check out Flower Shows at the Garden Web,
located on my links page.
*What
affect is this winter having
on perennials? (Minnesota)
It's hard to say obviously until spring. The fairly mild winter in
New England (1997, also 1998) should be good for them, until recently
when
wide temperature fluctuations melt snow, provide rain, this freezes
when
temperatures drop again, and so the lack of snow cover allows soil
temperatures
(what is more critical than the air temperatures for non-evergreen
herbacous
perennials)to drop to perhaps damaging levels. How low they drop, and
how
long they stay there will determine whether the perennials are injured.
*I
have a serious
problem with voles. I have tried many methods of ridding my garden of
them
while they continue ridding me of a garden. Any suggestions? (New
Jersey--I
get this question from all over, and have a problem myself in Vermont.)
I too have a similar situation and have tried many supposed remedies
including expensive sound emitters and solutions you pour on the soil
(basically
castor oil). I don't like poison baits as they tend to work up the food
chain and may kill domestic pets too. The only remedy I seem to have
any
luck with is a spring-type trap, baited with peanut butter, placed at
their
holes, with an inverted clay pot over the trap and hole (makes them
think
they're still underground). Cats also work, but I find you need two to
compete. Just one often tends to get bored and slack off on the
hunting!
*My
lawn has several birch trees and the grass has turned to moss. I would
like to gradually replace the grass with flowers and ground cover. Not
too expensively and I would like to do the work myself. I am a new
gardener.
(St. John's, Newfoundland)
You have a common problem to many. One option would be to live with
and enjoy a "moss garden", interplanting some ferns for texture and a
few
accent flowers for color like annual impatiens or perennial hostas for
bold texture or perennial astilbes for color. A groundcover which
should
do well is periwinkle or Vinca minor. Daffodils
should also provide
nice color and do well naturalized in such an area for early spring
color.
You should also check out the various search programs on my links
page--
general section. One is by Time Life. You can input your zone,
conditions
like shade, and it will come up with a list of the many other
perennials
for shade. Moss is usually a sign of moist soil, organic soil (both
good),
shade, or low pH (raise by liming per a soil test).
*When
is the Vermont Flower
Show, and who is speaking? (New York)
For dates and details, and schedule a month before, see the web site
at http://pss.uvm.edu/vfs/vfs.html
*I
didn't get
my bulbs planted in the fall. Is early spring okay? (Illinois)
Probably not, but for most bulbs which require cold you don't have
much other option from mid-winter on. Earlier (late fall, early winter)
you can plant in pots, keep at 40F for 3-4 months for their chilling
requirement
and rooting, then force indoors. Or you can plant out in spring as you
would a potted plant. Even if bulbs get their cold as in a
refrigerator,
if they aren't planted until spring they will immediately start growing
tops, without much roots, and so wont survive very well.
*Do you have
any suggestions on where and how
to buy good plants? (Vermont)
When buying plants, I always try to buy perennials in full bloom. I
know, you're probably thinking, as an experienced gardener why-- you
know
what the blooms will look like? "Will" and "should" are two different
things.
I often find plants mislabeled, often through no fault of the nursery.
This is also one reason I don't buy from the mass marketers-- often
they
don't know or often care what the labels say.
If a woody plant, it is easy to get the bare root plants from their suppliers in storage or shipping mixed up, and similarly for perennials. Or well meaning customers remove a tag to read, then put back on the wrong plant. (Try not to do this when shopping, speaking from experience!) After wanting a red this or yellow that for a specific purpose, and getting the wrong plant, I have come to this policy. The times I don't follow this are when buying from a very reputable local nursery that grows their own plants, or if buying the plant mainly for foliage. Often a good guide is a nursery that is a member of their state professional association, and has employees who have passed one of the many certification programs held by such associations.
Also, even when buying in color, I have to keep in mind that what I'll mainly see with perennials-- both woody and herbaceous-- is foliage, so must keep this in mind. The problem I've had with buying in color, is that for the first few years of gardening I never seemed to have time to get out to nurseries until later in the season-- hence my garden turned into mainly late blooming varieties! I've in recent years had to concentrate on either getting out sooner to buy, or buying those varieties which bloomed earlier in the season.
*I always
have a problem keeping plants labeled.
Do you have any suggestions? (Massachusetts)
As I've heard other experienced gardeners say, "the only thing worse
than a plant without a label, is a label without a plant." I've learned
you can't put this off, and must be religious-- get in a yearly or more
often habit-- about label maintenance. Now when I get home from the
nursery
with new plants I immediately make a more permanent label of my style
and
put in the pot so it will be there when planting. I've found I can get
a year out of a plastic label, and that #2 pencil is about the only
medium
that wont wear off in that time. I could get longer out of metal labels
but don't use them for 2 reasons-- the year cycle forces me to once a
year
visit every plant to check on it and replace the label (I need this
incentive
with over 1500 perennials), and with so many plants can't afford the
more
expensive labels (I do use them in more limited display gardens vs.
trials).
When I make the label, I also enter the plant on a list, which during the long winter months of Vermont I enter on the computer plant list. I also use this time to make up, by bed, all the labels for the coming year. And another tip-- when planting, if a whole bed or several varieties of the same plant-- make a map! I've lost too many plant identities with labels getting removed or just moved as in weeding to do otherwise.
*Do you have
any suggestions for how to keep
up with the weeds? (New Jersey)
If you have weeds, there is a reason. Something is wrong with your
culture. Weeds have a purpose, such as the tap rooted ones drawing up
nutrients
from the depths to the surface of impoverished soils. The main problem
is that nature doesn't like bare earth, and preferably likes it covered
with green foliage. So when planting I make sure I mulch heavily
(organic)
for the first year or two until plants are established. The goal is to
then have total coverage of the earth from the desirable plants, which
greatly minimized my weeding. I have friends and know gardeners who
like
discreet and individual plants with nice bark mulch between. There is
nothing
wrong with this, just realize that such culture means keeping the mulch
between plants thick and more maintenance in weeding.
*I have white
disease on the leaves of my garden
phlox, monarda and other plants. What can I do about this?
(Pennsylvania)
What you have is powdery mildew disease. It is basically favored by
humid or damp weather and moderate temperatures. Air movement, such as
from thinning stems and wider spacing often helps in landscapes. There
are also chemical sprays you can use, and horticultural oil is also an
organic option. The best solution is to plant resistant varieties to
begin
with. See my research on this and slides shows, under the sustainable
research
page, for much more on this disease and management.
*How can I keep
stray cats from digging in my
perennial garden? (Delaware)
Many catalogs and garden stores offer dog and cat repellents you can
put around the garden. Physical deterents such as chicken wire placed
on
the ground, above or under mulch, around desirable plants are effective
but rather cumbersome to install sometimes. Mulch which cats may not
find
conducive to digging, such as marble or brick chips, may also be
effective
(depending on the cats and their desires!). Of course other options
would
be to discuss with cat owners (if known) keeping their cats under
control
(some towns have pet ordinances), or fences.
*How
can I eradicate grasses that are
growing among my spreading junipers? (Minnesota)
You have a good question-- one I have a problem with too, only with
creeping phlox. There are some grass herbicides which only kill grass,
not broad-leaved plants. But make sure to read the label and follow
directions,
and make sure the plant you want to save wont be injured. If it doesn't
mention your desirable plant, it is always safer to try on a small area
first just to make sure. My solution though as I tend to try and avoid
such herbicides, is to dig up my phlox this year and either weed and
replant,
or replace with new varieties (actually what I've been meaning to do
for
some time now). It's a bit harder with plants such as junipers. I've
had
good luck with these though just putting on some long sleeves and
gloves
(to avoid their pricky foliage) and pulling back the branches to weed
underneath.
And I've learned from my own experiences to make sure the soil is grass
or weed free before planting!
*How can
I get rid of whiteflies? (Hamilton,
Ontario)
First, make sure you have whiteflies--they're pretty easy to see--
bascially white flies that swarm when you move plants. I always start
with
a soap based "organic" pesticide, which you mentioned has quit working
for you. There are a couple other whitfly products such as with
resmethrin
as an active ingredient, but you have to make sure they are labeled in
your case for vegetable use-- with food crops in greenhouses it can be
very tricky to control such pests. Often a soap-based product is about
the only remedy, and often the insects in their many and quick
generations
develop resistance to a particular pesticide. So if you find one that
works,
alternate with another about every 3rd or 4th time. Check your local
garden
stores to see what else they may have-- I'm always on the lookout when
traveling for a different safe product or two I can add to the arsenal!
For many insect pests you may also investigate the use of predator
insects
or diseases-- biological controls. There are more each year. Check some
of the links on my sources, products section from my links page.
*With
all the rain from El Nino this year,
are the black spots on my leaves a disease? (Los Angeles)
This definately could be a fungus if you haven't seen these before.
You might take a few leaves to your local garden center to be sure
though
and ask them-- also if so, while there, they can prescribe some control
I'm sure. Or check with your local land grant or state university, as
most
have a plant diagnostic clinic. (Your local Extension office also often
helps with diseases, or leading to such clinics.) Some plants though,
like
your impatiens, when they get too much water exude the excess through
their
leaf pores (stomates) and often form "water blisters"-- this is called
oedema. These can then discolor, forming "leaf spots" too. The only
control
for the latter is to try and keep the soil drier. This problem is
usually
seen with annuals and houseplants, and not too often with perennials
expcept
perhaps in a humid greenhouse.
*With
the mild winter my daffodils
starting coming up early this year. With the late snow and cold, will
they
be injured? (Vermont)
As with many answers, "it depends". If they only had an inch or two
of leaf tips, with the more tender buds still deep in the ground,
probably
not. If you can see a swelling at the base of the leaves (buds) and
leaves
are several inches long, probably so. If you have several inches of
mulch,
and leaves are just emerging, probably not. If bulbs are in a protected
place as near a warm foundation, or covered with at least several
inches
of snow during late cold, probably not. If in doubt, you can always
shovel
some snow on them, or add some straw (not weedy hay) around them (or
even
pine straw or other such loose materials) to provide additional
protection.
*I
would like to grow Lenten Rose
(Hellebore) as a groundcover for shade, but can't afford to buy the
expensive
plants. Can it be grown from seeds? (Massachusetts)
It can, but like many perennials, the fun is in the cultivars
(cultivated
varieties) which often don't come true from seed. If you're willing to
see what you get, and wait (often this takes 2 years or more to
germinate),
give it a try. These seeds often have "double dormancy", meaning they
need
to be sown and kept moist and cool (40F), warm (60F), then cool and
warm
again, each for about 2-3 months--hence the 2 years. The Hellebore or
Lenten
Rose is quite popular now, with many new cultivars, but keep away from
children as it is poisonous.
*I'm a new
gardener and would like to grow some
perennials from seeds. Which would you recommend? (Connecticut)
First keep in mind that the excitement with many perennials is the
cultivars (cultivated varieties), and that many of these can't be
propagated
from seeds for the young to resemble the parents. So if interested in
these
named cultivars, check your local garden center or many mail order
catalogs
now sell small plants (plugs) of many (see links page, sources
section).
Some easy perennials which are fairly reliable from seeds, and which
you
might try, include Columbine, Coneflower (Echinacea),
Early Sunrise
Coreopsis, Black-eyed Susans (Rudbeckia), Shasta
Daisy, Delphinium,
Hollyhock, Lupine, Oriental Poppy, Primrose, and Speedwell.
*What do you
recommend as good labels for the
perennial garden? (Virginia)
It really depends on several factors-- your climate, microclimate,
garden ethic, budget, number of plants, etc. There are some nice metal
labels on short stakes you can write on with special pencils-- very
nice,
but expensive if you have hundreds of perennials like me. On the other
end are the wood labels, or even popsicle sticks. Either pencil or
permanent
marker works on these, but these stakes will rot in a year or so and
the
names may be "sandblasted" off if windy. Although I'd rather not use
plastic,
I find I get at least a season from them, and pencil lasts the whole
year
(even in a hot sunny rock garden, or with our cold Vermont winters)
while
"permanent" marker does not . Plastic will crack after a year or so,
and
need replacing. I make up new labels during the winter from my master
list
(another good idea if you can get organized). Caution, when using
permanent
markers, use only black, as the colored inks usually only last a few
weeks
before they disappear! Of course check your local garden stores or
catalogs
for many other labels available that might suit your needs.
*Is there a
good computer program to help
pick plants and keep track of them? (Washington)
There are several software programs, many available at your local
bookstore
or computer software store, to help pick and design flower gardens. As
for keeping track of your plants, this is easily done on databases that
come with most computer packages or bundles. One that came with my
laptop--
Microsoft Works-- is the one I use, just setting up fields as I need
them
for scientific name, common name, year in, year died, bed, etc. You can
then pick by a certain trait, such as by bed, and organize such as by
common
name. Others that are more sophisticated but common include, but are
not
limited to, Access and dbase.
*Do
you know what varieties of lotus might
survive moderately cold Dutch winters? (Netherlands)
As I don't have specific experience with cultivars of this plant, you
should check some of the source links from my page on links, sources
section.
Many of these have some excellent cultural information as well as
listings.
I do know the species in general is listed for your winter temperature
range (zone 6, 0F/-20C), especially if located deeply in a pond below
the
frozen ice layer. It seems a key issue though for you is heat in
summer--
apparently this is needed for good bloom. A deep pond site obviously
would
survive winter better, but not provide as much heat as a shallow one.
So
it almost seems like additional heating of the water in summer might be
needed. If you had a raised bed, especially of dark color or material,
this should be warmer. Or perhaps you could rig a dark or black barrel
to absorb and heat water, which could then be slowly added to the pond.
*Something
is eating my hosta leaves.
What is it and what do I do? (Indiana)
Usually with hostas (funkia, plantain lily) this is caused by slugs
feeding at night. Check out my slug web site (yes there is one for most
anything) on my links page. Many have success just putting a board in
the
bed which they crawl under during day, and you can then find and remove
them. There are poison baits, but these can kill domestic pets as well.
The most popular remedy is saucers of beer, which attract slugs, and
then
they drown. The most effective though is probably copper strips-- slugs
wont cross them as they get shocked. Keeping lower leaves off for more
ventilation, and mulch removed for less dampness, help as well.
*How can
I overwinter tender perennials?
(Toronto, Canada)
I usually bring them in in pots and overwinter indoors in a cool area
such as cool (above freezing, below 45-50 degress) greenhouse, garage
or
hallway with window-- including some salvia, lobelia and some grasses
such
as the Red Foxtail (Pennisetum). Often I just leave these in pots
during
the growing season, sinking the pots in the ground either with or
without
another pot. The advantage to the "pot-in-pot" system is ease of
changing
plants, as you might change your furniture. This way you can keep
plants
in bloom in an area, rotating in new ones to replace finished ones. The
down side is that they get little moisture from the soil and require
more
frequent watering, which an automatic system with drip tubes to each
pot
or emitters can help. Tender plants may also be
overwintered by
covering with overwintering blankets (may be hard to find) or the
styrofoam
cones usually used for roses. These may provide some insulation, but
the
best insulator is snow.
*This season
my wooden stakes rotted. Is there
anything better to use? (Vermont)
My wooden stakes rotted too with all the rain, and I always have to
replace them yearly anyway. So this year I'm trying a method I saw at
Longwood
Gardens-- rebar. This is the reinforcing metal rod used in concrete,
and
available from most lumber and home building stores. I find 4 or 6-foot
lengths most useful, depending on the plant (4 ft. for peonies, 6 ft
for
asters for instance). I drive these 2 feet into the ground. For a bed
with
many delphiniums, I put in several, then weave twine between creating a
mesh for the plants to grow through. I also have used wise-mesh
fencing,
cut to make cylinders a couple feet across and placed over plants in
early
spring. These can be held in place with the rebar as well. I have also
seen the very wide mesh wire screen, again used to reinforce concrete,
used for cylinders to put over plants. Not only does this rust and
blend
in with the landscape, but it is sturdy enough to not need additional
staking.
*This year I
had quite a problem with deer eating
my perennials. What can I do, and are there any resistant plants?
(upstate
New York and others)
There are some methods you can use, depending on the severity of the
population, and some plants the deer tend to avoid. See my leaflet at http://www.uvm.edu/~pass/perry/oh64.html
for
details.
*I'm new to
growing perennials, and wondered
if there is a good book on color to help me design with them?
(Massachusetts)
Yes, in fact there are a couple books new in 1998 just on this topic.
These are reviewed on my Publications
Pages. Of course there is treatment of this to varying
degrees in many
general perennial books and books on perennial design as well, several
of which are also listed on the above page.
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some
linked here. Let the asker beware though of the
knowledge of
unknown "experts" or those without some credentials, especially if not
in your geographic area.
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