By Mary Welch-Keesey,
Purdue University Consumer Horticulture Specialist, at White
DO give your poinsettia at least six hours of bright sunlight during the holidays.
DO try to keep your poinsettia away from drafts, fluctuating air temperatures, excess heat and dry air from appliances, fireplaces or ventilation ducts. Poinsettias appreciate high humidity, so place them over a pebble tray or keep pans of water nearby.
DON'T expose your poinsettia to temperatures less than 50°F. Poinsettias are very sensitive to cold wind and temperatures. Keep plants covered when moving them from the store to a warm car and then to your house.
DO try to keep the temperature between 60° and 70°F, the cooler temperature at night. Keeping the plant at temperatures less than 60°F or greater than 70°F will encourage disease and shorten the life of the poinsettia.
DO keep the soil of your poinsettia plant moist. Water when soil feels dry to the touch or appears lighter in color. Add enough water so that the excess drains freely from the holes in the bottom of the pot.
DON'T let your poinsettia sit in water -- it may cause permanent root-rot damage. Remove the foil pot covering when watering so that excess water is not held under the pot.
DO keep your poinsettia after the holidays -- they make an excellent foliage plant.
DO let the plants rest for a few months after the holidays. Reduce watering and move to a dark location at 50°F. Water only enough to keep the wood from shriveling.
DO cut the branches back to 6" after growth resumes in May. The poinsettia may be grown in a south-facing window indoors (70-75°F) or outdoors, once night temperatures routinely exceed 50°F. Pinch to encourage a bushy habit, but not after mid-August.
DO fertilize every two to three weeks during this growing period (not while in bloom) with a balanced analysis fertilizer such as 10:10:10.
DO, if you have placed the poinsettia outside for the summer, move plants indoors when the weather starts its annual fall temperature fluctuations, usually by late August.
DO provide at least 14 hours of darkness starting October 1st.. Poinsettias must experience long nights in order to form flower buds. Place in an environment where the dark will not be interrupted, even briefly, by turning on a room light or by a streetlight. If this happens, the plant will experience two short nights, instead of one long one, and flowers will not form. Continue this schedule for approximately ten weeks to get the plant blooming for the holidays.
DO keep the plants in a room where the temperature is less than 70°F at night when exposing them to the short day/long night treatment.
DO keep poinsettias away from animals and children. Contrary to popular belief, they are not poisonous but like most ornamental plants, they should not be eaten.
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