How to Grow and Care for Poinsettias
About Poinsettia
Poinsettia (Euphorbia pulcherrima) grows 3 to 10 feet tall and is hardy in USDA zones 9 to 11. It grows best in part sun to part shade with medium water.
Poinsettia is a perennial shrub with green leaves and clusters of tiny yellow flowers surrounded with large colorful floral bracts. The bracts are modified leaves that are often thought of as the flower. The plant is most popular in decorated pots for holiday décor and festivities. They can be grown outdoors during summer as a green leafed shrub. The shrub is not cold hardy, so must be brought indoors with temperatures below 50 degrees. They come in a variety of sizes for indoor use but in warmer climates, can be grown outside to 3-10 ft tall and 3-7 feet wide. The colorful bracts attract insects to the flowers which drop after pollination. Poinsettias prefer moist well drained soil and part sun 4-5 hours daily. Special care is required to produce the showy winter blooms. Poinsettias come in a variety of colors from creamy white to pink to the traditional bright red. It is native to Mexico where it grows 10-15 feet tall. It’s name was in honor of Joel Roberts Poinsett, botanist and Ambassador to Mexico. He introduced the plant to the United States in 1828. Poinsettias are not poisonous to humans and pets, but should not be eaten as it may cause mild symptoms. The white sap may cause a skin rash, so best to handle with gloved hands and avoid contact with eyes and mouth.
When to Plant Poinsettias
Poinsettias are sold as holiday houseplants. Outdoors in zones 9 to 11, plant them in spring after frost danger passes.
How to Plant Poinsettias
Grow poinsettias from seeds or from cuttings. Take cuttings from new stems about 4” long with at least 2 new leaves. In a pot with a moist seed starting mix, immerse cutting half way. Use a rooting hormone to encourage healthy root development. Cover with a clear plastic bag to trap in the moist air. Place in bright indirect light, with temperatures 60-70 degrees. Mist the soil as needed to keep it moist. After about 3-4 weeks, the plant should root and begin to show new growth. Then remove the bag and fertilize once a month.
Poinsettia Care
Water potted Poinsettias in full bloom whenever the soil feels dry to the touch, about once a week. Water thoroughly and let drain out completely through the drain holes. To avoid root rot, do not stand in water. To extend its bloom, maintain a temperature of 65 to 75 degrees Fahrenheit and place near a sunny window for six to eight hours of diffused light per day. Once the blooms drop off can transplant into a 2-4 inch larger container with good drainage. Use a soil mix with lots of organic matter such as peat moss. Prune and cut back to encourage new growth. In warm year round climates, can transplant into garden bed with well-drained soil. In the summer, potted plants can be moved outside. Bring back inside well before temperatures fall below 60 degrees at night. Outdoor plants should get 4 to 5 hours sun per day. In warmer climates, morning sun and afternoon shade is ideal. To force re-blooming of the flowers and colorful bracts, in September, bring indoors and stop fertilizing. Keep in complete darkness for 14 hours and in indirect sunlight for ten hours daily for 4-5 weeks. Continue normal care when the bracts change color.
Fertilizing Poinsettias
Do not fertilize when in bloom. Begin fertilizing when you see new growth. Use an all-purpose household plant fertilizer, diluted water at half strength. Feed every 3-4 weeks.
Pruning Poinsettias
Prune as needed to remove damaged areas. To encourage growth after the blooming season, cut stems back to about 4″. For strong side branching, trim out some the new stem growth.
Poinsettia Pests and Diseases
Poinsettias are susceptible to variety of diseases and pests such as gnats, white flies, thrips, mealybugs and powdery mildew. Remove affected areas of the plant and treat with an insecticide or fungicide until the problem is gone.
Are Poinsettias Toxic to Cats and Dogs?
Poinsettias are only mildly toxic. The ASPCA notes the milky sap can cause mild mouth irritation and vomiting in dogs and cats, but serious poisoning is rare. If you think a pet has eaten a toxic plant, call your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435.
Poinsettia FAQs
How do I keep a poinsettia alive after Christmas?
Keep it in bright, indirect light away from drafts, and water when the soil surface feels dry. Remove the foil wrapper so water can drain.
How do I get a poinsettia to turn red again?
Starting in early October, give it 14 hours of complete darkness every night for about eight weeks, with bright light during the day.
Why is my poinsettia dropping leaves?
Cold drafts, sudden temperature changes and overwatering are the most common causes.
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