Poinsettias were introduced into the United States almost 200 years ago by Joel Poinsett, the first U.S. Ambassador to Mexico. They were given the common name poinsettia in his honor.
Over time, poinsettias have become the best-selling flowering potted plants in the U.S. They are tidy attractive plants with clusters of several colored leaves, or bracts. Bracts are typically red, pink or cream and are often mistaken as part of the flower. However, actual poinsettia flowers are small and yellowish green; they are located within the bract clusters.
When choosing a plant to purchase, look for one with healthy foliage. Do not purchase a plant that is wilting, yellowing or has dark colored leaf spots. Transport your plant from the store to your home by minimizing temperature/wind extremes and preventing leaf and stem breakage. Plant injury will result in the exudation of a milky white sap or latex that might discolor fabric and irritate skin.
Most people treat poinsettias as annuals and purchase new ones each winter season, but in their native region they are actually perennial shrubs. In Mexico, the country where poinsettias were first discovered, a single plant might grow more than 10 feet tall. Plants sold in local stores have been bred and treated to be much smaller.
Although we do not have the optimal poinsettia growing conditions in our region, it does not mean that we cannot keep them for an extended period. The requirements needed to keep a poinsettia looking its best are sunlight, a temperature between 60 and 70 degrees and adequate moisture. The best place to display a plant is in a sunny, cool room away from direct sunlight, heating units, fans, doors and return air vents.
Watch your plant to find its ideal living conditions in your home. If the entire plant wilts, you likely need to give it more water. If the plants' leaves wilt and then fall, you might be providing too much moisture. If the leaves fall without wilting, there could be a problem with the temperature or the amount of light. If the leaves curl, turn yellow, and then fall, the plant is likely suffering from drought, high temperatures and insufficient lighting. Tips to correct these problems include checking the soil with your fingers to determine if the plant needs water and moving your plant to a different location within your home.
Beside environmental factors, your plant might also be affected by insects or disease. Spider mites and mealy bugs are two common insect pests. Potential diseases include infections caused by bacteria, fungi or viruses. If you suspect an insect or disease call the Extension office for advice on how to best manage the problem.
If you are up for a challenge this winter season and next year, consider keeping your poinsettia until next year. The process includes pruning, fertilizing and light manipulation. Step by step information is available on the University of Maryland website for the Home and Garden Information Center at www.hgic.umd.edu. Click on Publications, Online Publications, Seasonal and Indoor Plants, and then HG 30. Alternatively, you might contact me at the University of Maryland Extension-Washington County on weekdays by calling 301-791-1604 or by email at email@example.com.
Karen Sechler is a horticulture educator with the University of Maryland Extension in Washington County. She can be reached by calling 301-791-1604 or sending an email to firstname.lastname@example.org.