While very beautiful, Poinsettias are suprisingly birttle. The branches will easily snap if handled without care, and cold drafts will harm them significantly. The leaves (lamina) are also thin and grow up to 20 inches long. Good drainage is required, and the soil must be somewhat dry on a regular basis. Nevertheless, the colorful and extravagant bracts (modified leaves) make Poinsettias extremely popular, especially during the holiday season. There’s a good reason their species name is pulcherrima (Latin for “the most beautiful” or “very pretty”).
Euphorbia pulcherrima (Poinsettia, Christmas Star, Christmas Flower)
Subspecies: ‘Rosea’, ‘Ecke’s White’, Barbara Ecke Supreme’, and many more
Native: central America
Hardiness Zones: 9-11
Height: 1.5-3 meters in cultivation, naturally to 4.5 meters in its native habitat (Mexico)
Diameter: 1-2 meters in cultivation
Root System: brittle, easily disturbed, fibrous but become woody with age
Growth Rate: Fast (if given ammonium fertilizers when not flowering), maximum growth rate occurs at around 65 degree Fahrenheit nights and 75 degree Fahrenheit days.
Tolerates: very few stressors in cultivation
Problems (major): Temperature higher than 70 degrees Fahrenheit reduces bloom time while lower than 50 degrees Fahrenheit can be lethal. Root rot, stem decay, mealybug infections, brittle system overall
Problems (minor): white sap (dermatitis), red spider mites,scale insects, whitefly
Poisonous: Contrary to popular belief, they are not poisonous (yes, the bracts are nonpoisonous as well). The University of Ohio apparently ran an experiment disproving the alleged dangers of the bracts. Ingesting any part of a Poinsettia has shown few, if any, adverse effects.
Soil requirements: Fertilizer usually isn’t necessary if grown solely as a holiday plant in winter only. Fertilization is rarely needed after blooming in spring and summer (monthly proves to be successful).
Air Requirements: warm air, around 65 Fahrenheit at night and 75 Fahrenheit during the day
Watering requirement: water once the surface dries, prefer to be moderately dry, good drainage essential.
Sun requirement: full sun or part-sun
Leaves: diamond-shaped, dark-green, prominent yellow venation, to 20cm long by 15cm wide
Flower structure: small clusters (“cyathia”) surrounding by red/pink/white/yellow bracts resembling petals in winter/spring
Flowering frequency: requires up to 12-14 hours of darkness (late autumn, winter) to bloom (conversion of leaves into bracts known as photoperiodism)
Fruit type: small, irregularly shaped seed pods
Fruit dispersal: likely birds
The large, showy, red or pink bracts give this plant a gorgeous appearance. The bracts are actually leaves that have been modified to change color through a process called “photoperiodism”. These plants are unfortunately frail, although their immense beauty has led to their enormous populatization around holiday season.
Very popularly used as an ornamental, especially around Christmas. Not recommended as a food source.
The images provided were taken by me and can be used for educational purposes if this blog is appropriately cited.