The poinsettia, the most popular holiday plant, is best known as the plant with bright red flowers on a green background. But, the showiest part of the poinsettia is the group of colorful specialized leaves called floral bracts that surround the small, yellowish-green structures that are the true flowers, said Michael N. Dana and B. Rosie Lerner (retired), Purdue Extension specialists.
Dana and Lerner said red is still the most popular color, but bracts may also be pink, salmon, yellow, white or multi-color.
The long-lasting nature of today's poinsettias can only be enjoyed if they receive the proper care in your home. They said the best way to extend their beauty is to match, as closely as possible, the conditions in which they were produced. Poinsettias are raised in greenhouses where temperatures can be maintained between 65 -75 degrees F with high relative humidity and high light intensity.
These conditions will be difficult, if not impossible, to match in the home. Natural light intensity tends to be quite low and of shorter duration in the winter. And as we heat the air indoors, the air becomes drier so that relative humidity often drops below the level of plant and people comfort.
Dana and Lerner suggested making the most of the situation by placing your plant near a sunny window, but not to allow the foliage or flowers to contact cold window glass. Artificial light may be needed for extended growing periods. A humidifier will increase both plant and people comfort. Grouping plants together on a pebble tray will help raise humidity around the plants themselves. Both hot and cold drafts can cause leaf drop, so avoid placing plants near doors or heating vents.
Both under- and over-watering can decrease the life of your plant. Plants that are allowed to wilt will begin to brown along the edges of the leaves and floral bracts or may drop leaves entirely. Watering too often will prevent proper aeration of the soil, and roots will begin to decay. Poinsettias should be watered when the top inch of soil feels dry to the touch. If your pot was wrapped in foil, be sure to poke a few holes through the bottom to allow excess water to drain away.
If you're giving a poinsettia as a gift, Dana and Lerner said to be sure to protect it from frigid outdoor temperatures during transport. If you make your purchase from a florist or other supplier, be sure they wrap your purchase. Get the plant from the store to your car as quickly as possible. Preheat the car beforehand to prevent further chilling injury. Plants left in an unheated car can be injured or killed quickly, so drop the plants off at home before running other errands.
“The poinsettia has long been veiled in an aura of folklore and has gained the reputation of being a deadly plant,” wrote Dana and Lerner. In university tests, they said rats showed no signs of toxicity or any apparent ill effects when given large doses of homogenates made from the leaves, bracts, or flowers of the poinsettia. The force-fed rats showed no changes in dietary intake or general behavior pattern. “So, it appears the poinsettia is not a dangerous plant as many people still believe,” they said.
Poinsettia is a member of the Spurge family (Euphorbia spp.). Some people and pets may be sensitive to the plant’s milky sap (common in spurges), resulting in skin irritation when skin is in contact with that sap.
With that said, it is always best to keep plants out of the reach of children and pets. If consumed by pets, the Purdue Extension booklet, “Indiana Plants Poisonous to Livestock and Pets,” states that plant parts can irritate the lining of the mouth and stomach. “Although there usually are no further ill effects, nausea and vomiting may follow,” it says.
More information on the poinsettia, such as reflowering, care throughout the year, and propagation can be found in the Purdue Extension publication, “The Poinsettia,” authored by Dana and Lerner. Find it at www.edustore.purdue.edu.