Monday, November 22, 2010
Deb Babcock's gardening column appears Mondays in Steamboat Today.
Find more gardening columns here.
Poinsettias are the top-selling flowering potted plant in the United States.
Native to Mexico, these beautiful plants are especially coveted during the holiday season. The showy and brilliant red, pink, white, yellow, and multi-colored bracts (leaves) are their most resplendent in November and December, when they come into full bloom.
When choosing a poinsettia, look for plants with stiff stems and no lower leaves missing. Since a poinsettia requires lots of space, be wary of those that have plastic, paper or mesh coverings, as extended time in such a restricted space can harm the plant. Avoid plants with waterlogged soil; it could be a sign of root rot, which is irreversible.
Protect your poinsettia during the trip home from the store. The low temperatures and chilling winds of a Steamboat winter, even for a short drive home, can damage the leaves and bracts.
At home, place your poinsettia in a location that will provide at least six hours of indirect, natural daylight. If needed, diffuse the bright light with sheer curtains or other foliage. To keep the bracts brightly colored, daytime temperature should not exceed 70 degrees F nor go below 60 degrees F at night.
Your poinsettia does not need to be fertilized while it is in bloom and should have moderately moist soil, but don’t allow the pot to sit in standing water.
If you wish to keep your poinsettia for reflowering next year, cut it back to about 8 inches in height in spring when the bracts start looking old and worn out. Within a couple of months, you should see vigorous new growth. Keep watering and fertilize regularly. Repot to a slightly larger container. Prune when needed, but no later than Sept. 1, to keep your plant nicely shaped.
Poinsettias are photoperiodic plants, which means they set their buds and produce flowers when the fall nights become longer, blooming naturally during November and December.
Getting the plant to bloom in time for Christmas is tricky.
In October, they must be kept in complete darkness for 14 continuous hours in 60 to 70 degree temperatures; light from streetlights, lamps or outdoor house lights might delay or stop the reflowering process. You might consider covering the plant with a paper bag or upside-down wastebasket to achieve this continuous darkness. During the day, your plant will need six to eight hours of bright sunlight during October, November and December. This 14-hour darkness treatment should last until the plant begins to show some color in the bracts, usually around Thanksgiving.
The widely held belief that poinsettias are poisonous is wrong. While poinsettias are not an edible plant, they are not toxic if eaten. Research at Ohio State University, in cooperation with the Society of American Florists, concluded that no toxicity was evident at experimental ingestion levels far exceeding those likely to occur in a home. Even if a 50-pound child ate more than 500 poinsettia bracts, no toxicity would be found, according to POISINDEX Information Service, the primary information resource used by most poison control centers.
So, that said, enjoy the bright colors of this favorite holiday plant.
Deb Babcock is a master gardener through the Routt County Cooperative Extension Office. Call 970-879-0825 with questions.