Poinsettia (Euphorbia pulcherrima), also called Christmas flower, is a tropical shrub native to Mexico and Central America. This plant has become a holiday staple in the United States, boasting modified leaves called bracts. These plants come in a variety of colors, but red is still the most popular by far. While commonly available in the month of December, this plant can be kept alive for many years if properly cared for.

       Being native to Mexico, this plant lacks cold tolerance and temperatures below 50 degrees Fahrenheit should be avoided for extended periods. Drafty areas of the home, such as doorways and windows with poor insulation or seals should not be chosen to keep a poinsettia. These temperature swings and cold exposure may result in significant leaf drop. This being said, a poinsettia benefits greatly from intense light exposure. A bright window is often sufficient to keep them happy and keep their intense color.

       This plant often inhabits dry forests in its native range, and a potting mix that is well draining is an ideal choice. Water the poinsettia based on the weight of the pot. If the pot is light, water deeply until the excess can drain. If the pot is heavy, it does not need water. Overwatering is the primary cause of death for these plants. If the pot is wrapped in decorative foil, remove the pot for watering to ensure there are no blocked drain holes.

       While the genus Euphorbia contains many plants with toxic latex sap, the poinsettia is relatively harmless. The latex contained in the stem and leaves can be a mild irritant for the skin, eyes, and mouth. Contact should be avoided, particularly if an individual has a latex allergy. Soap and warm water if usually sufficient should the sap come in direct contact with human skin. This plant is also not dangerous for cats or dogs, contrary to popular belief. However, plants should still be kept out of reach for both curious children and pets. Consumption may result in vomiting and excessive saliva.

       Once the bracts and blooms fade, these plants can be kept as a houseplant all year if desired. After the last frost, they perform well if grown outside with some protection from the harshest of the afternoon sun. To keep the compact form, pruning in spring to promote new growth is important. Plants should also be pinched regularly to promote dense branching prior to flowering again. Fertilize using a balanced product (ex. 10-10-10) according to label instructions through the summer.

       To induce flowering, plants must receive at least twelve hours of total darkness per day. Begin this process in September to have beautiful blooms come December. A dark closet is a suitable location, where the plant cannot access any light. Placing the plant in the dark starting in the evening, left overnight, and brought back out the following morning is the simplest routine.

A variety of poinsettia plants at Poinsettia Field Day in a Raulston Arboretum greenhouse.