Perry's Perennial Pages

Frequently Asked Questions (FAQs) on Perennials

Can't find your answer?  Then if you have certain browsers such as Mozilla Firefox or Explorer, go to Edit>Find in Page at the top and type in keywords for what you are searching.  Still can't find your answer?  Then go to the resources at the bottom of the page.

Latest Additions

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?

Care and Culture

What's wrong?

General

The 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)

*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 m