- Nancy Doubrava, HGIC Information Specialist, Clemson University.
- Bob Polomski, Extension Consumer Horticulturist.
The poinsettia (Euphorbia pulcherrima) is the most popular flowering plant sold in the United States with more than 70 million sold nationwide each year. When South Carolinian Joel Poinsett, the first U.S. ambassador to Mexico, introduced the poinsettia to the U.S. in 1825, it’s doubtful he had any idea how popular this plant would become.
Plant breeders have produced cultivars with many other colors besides the traditional red bracts, or modified leaves. Plants are available with white, pink, peach, yellow, marbled and speckled bracts. The actual flowers of the poinsettia plant are the small, yellow blossoms in the center of the colorful bracts.
KEEP YOUR POINSETTIA BEAUTIFUL
To help your poinsettia thrive in your home during the holiday season, follow these tips:
Light: Set your poinsettia in a bright location so that it receives at least 6 hours of bright, indirect sunlight each day. Putting it in direct sunlight may fade the color of the bracts. If direct sun cannot be avoided, filter the sunlight with a light shade or sheer curtain.
Temperature: Excess heat will cause the leaves to yellow and fall off and the flower bracts to fade early. The daytime temperature should not exceed 70 °F. Do not put your poinsettia near drafts, excessive heat or dry air from appliances, fireplaces or ventilating ducts. Chilling injury is also a problem and can cause premature leaf drop if the temperature drops below 50 °F.
Water and Fertilizer: Poinsettias require moderately moist soil. Water them thoroughly when the soil surface feels dry to the touch. Never let the potting mixture completely dry out and never let the plant sit in standing water. When watering, always take the plant out of its decorative pot cover. Water until water seeps out of the drainage hole and the soil is completely saturated. Do not fertilize a poinsettia when it is in bloom.
CARE AFTER THE HOLIDAY SEASON
Around March to April, when the colorful bracts fade, prune the plant back to about 8 inches in height. Although the plant will look bare after pruning, eventually new growth will emerge from the nodes up and down the stem. Keep the plant near a sunny window and continue to water it regularly during its growing period. You can take the plant outdoors once the night temperature remains above 50 °F. Fertilize the plant every two to three weeks during the spring, summer and fall with a well-balanced complete fertilizer such as 10-10-10.
In early June, transplant the poinsettia into a container 2 to 4 inches bigger than the original pot. Use a soil mix containing a considerable amount of organic matter, such as compost, leaf mold or peat moss. Pinch back the shoot tips or prune back the branches. Do not pinch back after September 1. When night temperatures become cool, 55 to 60 °F, bring the plant indoors to a sunny location.
REFLOWERING A POINSETTIA
Poinsettia plants can be brought back into flower next year, although this procedure is somewhat demanding. Poinsettia is a short-day plant, which means it needs a continuous long dark period each night to form its colorful bracts. Starting the first week of October (for an eight- to 10-week period) the plant must be kept in total darkness for 14 continuous hours each night. Keep the plant in darkness by moving it to a closet or covering it with a large box. During this period, the plant must also receive six to eight hours of bright sunlight daily. Depending on the response time of the particular cultivar, the plant will come into full bloom during November or December.
Pests that attack poinsettias are also common to many other plants. The most common insect pest is the whitefly. Other pests of poinsettia include mealybugs, soft scales and spider mites. Root rotting fungi can occur in overwatered or poorly drained soils. Several factors can cause premature leaf drop, such as temperatures dropping below 50 °F, poor light or poor nutrition. Keep the delicate colorful bracts well-protected from wind and cold rain.
Center Publication Number: 158