Euphorbia pulcherrima

The poinsettia is a deciduous to semi-evergreen shrub or small tree in the spurge family (Euphorbiaceae). The plant is native to Mexico and Guatemala, and it was brought to the United States in the early 1800s by Joel  R. Poinsette, botanist and ambassador to Mexico. The specific epithet, pulcherrima, is Latin for “beautiful." In its native habitat, this plant is found along the coast and in dry tropical forests and can grow up to 10 feet high and 8 feet wide. It is typically grown as a potted plant, and it rarely exceeds 2 to 3 feet. In the United States, poinsettia is commonly purchased as a decorative florist plant during the Christmas holidays.

The plant grows best in part shade at temperatures of 65 to 70 degrees Fahrenheit. Keep this plant away from heat vents, fireplaces, and cold drafts. Water the plant when the soil surface feels dry, but do not overwater. The soil should be well-drained, potting mix of loam, organic matter, and peat moss. The plant is winter hardy in USDA Hardiness Zones 9 to 11. If planted outdoors, the plant should get 4 to 5 hours of sun per day. To maintain the plant in the garden, begin fertilizing in the spring. Prune or pinch back through the summer to promote the growth of the main branches. To propagate poinsettias, use stem cuttings in early summer with rooting hormone and potting mix that contains peat moss, perlite, and vermiculite.

The cup-shaped yellow "flowers" bloom in the winter through the spring and cluster above showy red leafy bracts or modified leaves. The true flowers are egg-shaped, yellow, and appear at the base of the bracts. A large yellow gland on the rim of the "flower" adds to its decorative appeal. Poinsettias are available commercially in a variety of bract colors including shades of red, pink, white, and orangish-peach. Some varieties have bracts that are red and white, pink and white, or green and white. The foliage is dark green, ovate with margins that may be entire, lobed, or dentate. The stems and leaves produce a milky sap when cut or torn.

After blooming, the poinsettias can become attractive green plants, and they can be grown outdoors during the summer. Many people would like their poinsettia to be colorful again for the next Christmas season. This requires a lot of effort, and the plant must be healthy. Starting in late September, the plant will need 16 hours of uninterrupted darkness and 8 hours of bright light daily plus night temperatures in the low 60s to produce the red, pink, or white bract color for Christmas.

The poinsettia holds the largest share of potted plant sales during the Christmas season. For cooler climates, it is best used as a florist plant and grown outdoors during the summer. In warm climates, it can be planted outdoors or used as an accent in the garden or a container plant.

Insects, Diseases, and Other Plant Problems: Monitor for mealybugs, red spider mites, scale, and whiteflies. Overwatering can cause root and stem rot. The plant stems are very brittle and break easily. Handle with care. 

Poinsettia plants have a low severity as far as being poisonous. Studies have shown that a significant amount of the plant would have to be ingested before registering a mild stomach ache. However, the white sap can cause reactions in people who have latex allergies. Wear protective gloves when handling this plant and keep sap out of your eyes.

VIDEO Created by Homegrown featuring Ingram McCall, Research Specialist at NC State University

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