University of Vermont Extension 
Department of Plant and Soil Science

 Winter News Article

Dr. Leonard Perry, Extension Professor
University of Vermont

[Polish translation of this article]
Poinsettias have become synonymous with the holiday season. In fact, December 12 has been proclaimed by an Act of Congress as National Poinsettia Day to commemorate the death of Joel Poinsetta who introduced this Mexican native plant to the U.S.   Many varieties have been developed over the last few decades, with currently well over 100 different varieties in a range of flower colors and styles.  To get the longest life and enjoyment from the ones you purchase or receive as gifts, follow a few simple tips.
Start with proper selection. This means choosing plants with healthy, dark green foliage and brightly colored "bracts".  Bracts are actually colored leaves that look like flower petals, but aren't.  Poinsettias are available with red, white, pink, peach, yellow, marbled (pink and white patterns), or bi-colored bracts.  Still most poinsettias grown and sold are red, but if you want to be different, or "design" with them, look for one of these other colors. 
Some of the newer selections include red with white spots as in the cultivars (cultivated variety) with the name 'Jingle Bells'.  There are variations in pink from bright to a soft peppermint to rose to salmon.  One of my favorites has cream, rose and pink, and goes by the name 'Monet Twilight'.  Reds range from bright to dark maroon, almost purple. Some "marbles" can be white and pink in roughly equal amounts, or more of one color.  There are even double flowers with more bracts, such as the red 'Valentine' and the Winter Rose series containing several colors.  There is even a red poinsettia with green and white variegated leaves.
Green leaves should be just that, not yellowing or falling off, signs of poor culture and temperatures.  Don't buy drooping plants, a sign they've been stressed from lack of water.  If a plant is wilted, but the soil is wet, the plant may have a root rot disease.  Plants crowded together for more than a few days may lose bracts prematurely. 
The "true" flowers are found in clusters in the center of the colored bracts, and are called "cyathia". Poinsettias are technically in flower when these pollen-bearing clusters are open.  Longest life comes from choosing plants with these cyathia not yet open, or just opening.
You should consider the shape and proportion of the plant. While plant height and pot size aren't significant individually, the relationship between them is important for the best-looking plant. The ratio of plant-to-pot size should be about two to one (a 12-inch plant in a six-inch pot, for example.)
Poinsettias are extremely sensitive to cold and freezing temperatures, so make sure your plant is wrapped when carrying it between the store and your car when outdoor temperatures are below 50 degrees (F). Never transport it in the trunk where it is apt to freeze, even in protective wrapping.  Buy on warmer days if possible.
If you are concerned that poinsettias are poisonous, don't be.  This myth was based on a false report many decades ago.  Poinsettias have been shown by scientific studies at Ohio State University to not be poisonous, and poisonous plant books only list occasional cases of vomiting if enough leaves are ingested.  To avoid even this, keep plants away from children and pets as you would harmful household products.
To enjoy your poinsettia for as long as possible, place it in an area with sufficient natural light to read fine print, and away from heat outlets and drafts from open doors and windows. At least 6 hours of direct light daily is ideal. Ideal day temperatures should be between 60 and 70 degrees, nights between 55 and 65 degrees.          
Provide uniformly moist soil with good drainage.  It's better to let plants get a bit dry than to keep too wet, causing roots to rot. If pots are in saucers, don't let water remain in saucers.  If pots are in decorative foil, punch a few holes in the bottom to allow excess water to drain.
Poinsettias benefit from regular fertilization after bloom. Use a complete, water-soluble fertilizer at the rate and frequency recommended on the label. With good care in the home, poinsettias often retain their colored bracts for four to six months, or even longer.  Most tend to tire of seeing these long before their bracts have faded.
If you do decide to hold your poinsettias until next fall, remember that they need darkness (13 hours, uninterrupted, as in a dark closet) every night from the end of September to Thanksgiving.  Just remember to take plants out of the dark during the day and to give bright light.  Most find it easier to buy new ones each year, with plants of better quality having been grown under ideal greenhouse conditions. An early December visit to a local greenhouse, full of thousands of plants all in bloom, makes a memorable outing all should experience if the chance.

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