Poinsettia

Euphorbia pulcherrima Willd. ex Klotzsch · Euphorbiaceaealso known as Christmas star, Christmas flower, Mexican flameleaf

The bright red bracts of poinsettia (Euphorbia pulcherrima), often mistaken for petals, surround tiny yellow flowers. This arrangement gives the plant its recognizable winter appearance.

↔ swipe · 4 photos

Bracts and true flowers

What most people think of as flowers are actually colored bracts. The true flowers are small and yellow, grouped in rosette-like flower clusters at the center of the shoot tip.

The leaves are dark green, ovate to elliptical, with toothed edges. The leaf blades reach 10-15 cm in length and are attached by petioles.

  • dark green, ovate to elliptical leaf blades
  • small yellow flowers in rosette-like clusters
  • red bracts or other colors depending on the cultivar

The bracts define the plant's seasonal appearance. Their color can vary by cultivar, while the structure of the flower cluster is easy to miss without a close look.

Origin and name

The plant is native to Mexico and Central America. In the wild, it is an evergreen shrub that can reach 3 m tall.

Low-growing hybrids under 30 cm are common as houseplants. Their size does not change the plant's botanical identity: it belongs to the genus Euphorbia and has its characteristic milky sap.

The Ukrainian name meaning "Christmas star" refers to its December-February flowering period and the star-shaped arrangement of its bright bracts; it is a common and trade name, not a botanical term.

Light and placement

Poinsettia likes plenty of light, so choose a well-lit spot. In shade, the plant may retain its leaves, but its seasonal display of bracts is usually less pronounced.

Avoid drafts, especially during flowering. Abrupt changes in conditions after purchase often show in the leaves: they may wilt or drop.

Near a window, stable conditions matter as much as light levels. The plant does better in a sheltered spot without cold airflow.

Watering and feeding

Water moderately: the potting mix should not stay constantly wet. In summer, when growth is more active, water more generously, but do not let water stand.

Reduce watering after flowering. At this stage, the plant moves from its display phase into recovery, so excess water around the roots is especially unwelcome.

In spring and summer, feed 2 times a month with a compound mineral fertilizer. During flowering, use potassium fertilizers if the plant is still maintaining its bracts.

Pruning and repotting

After flowering, cut the shoots back to a height of 10 cm. This is part of the care cycle, not a sign that the plant is dying: the old bracts have already served their purpose.

Repot about 2 months after pruning. Until then, keep watering limited so the roots do not remain in overly wet conditions.

Pruning releases milky sap. It can irritate skin, so avoid touching cut surfaces and tools unnecessarily.

Flowering and cultivars

Flowering occurs in December-February. During this time, bright bracts form around the small yellow flowers, giving the plant its recognizable appearance.

The classic bract color is red. Cultivars with yellow, pink, purple, and bicolored bracts have also been developed.

Compact hybrids are often grown indoors. They are more manageable than the wild form, which is described as a much taller shrub in its native range.

Toxicity and common risks

The plant is mildly toxic to cats and dogs. Its milky sap can irritate skin, and eating it may cause nausea, vomiting, or diarrhea.

The danger should not be overstated, but contact with the sap is best limited. This is especially relevant during pruning and repotting, or when a pet chews the shoots.

  • skin irritation after contact with the sap
  • nausea or vomiting after eating parts of the plant
  • diarrhea in response to swallowed plant material

If sap gets on the skin, wash it off with water. If a pet eats part of the plant and symptoms persist, consult a veterinarian.

Characteristics
Light
light-loving
Watering
moderate, generous in summer
Difficulty
moderate
Cats and dogs
mildly toxic
Size indoors
less than 30 cm in hybrids
Leaves indoors
10-15 cm
Native range
Mexico and Central America

Care

Poinsettia has a distinct seasonal cycle: it retains its bright bracts during flowering, then needs reduced watering and pruning afterward. The main indoor risks are drafts, overwatering, and contact with its milky sap.

Light
Provide bright light. A light-loving plant; choose a well-lit spot indoors without abrupt changes in conditions.
Temperature
Keep away from drafts. Avoid drafts, especially during flowering and while the plant adjusts after being moved.
Watering
Water moderately. Water moderately during growth and more generously in summer. Reduce watering after flowering.
Feeding
Feed 2 times a month. Apply a compound mineral fertilizer in spring and summer; potassium fertilizers are suitable during flowering.
Leaves
Avoid contact with the sap. The milky sap can irritate skin, so avoid direct contact with cut surfaces when pruning.
Repotting
Repot after 2 months. After flowering, cut the shoots back to 10 cm, reduce watering, and repot after about 2 months.

Botany

4 ill.
Taxonomy
Family
Euphorbiaceae
Genus
Euphorbia
Species
Euphorbia pulcherrima
Author and year
Willd. ex Klotzsch
Botanical illustration, 1873
Botanical illustration, 1873 · unknown author, Public domain
Botanical illustration, 1880
Botanical illustration, 1880 · Francisco Manuel Blanco (O.S.A.), Public domain
Botanical illustration, 1880
Botanical illustration, 1880 · Francisco Manuel Blanco (O.S.A.), Public domain
Botanical illustration, 1880
Botanical illustration, 1880 · Francisco Manuel Blanco (O.S.A.), Public domain
↔ swipe · 4 illustrations

Poinsettia belongs to the family Euphorbiaceae and the genus Euphorbia. Like many spurges, it has milky sap that is released when shoots or leaves are damaged.

In the wild, it is an evergreen shrub up to 3 m tall, native to Mexico and Central America. The leaves have petioles and are dark green, ovate to elliptical, with toothed edges.

The display comes not from petals but from bracts that develop around the small yellow flowers. In cultivated varieties, these can be red, yellow, pink, purple, or bicolored.

How it differs from similar plants

Crown of thorns Euphorbia milii
Euphorbia milii has bright, rounded bracts above thorny, fleshy shoots, while poinsettia's bracts surround small yellow flowers without those thorns.
Garden croton Codiaeum variegatum
Croton is recognizable by its leathery, variegated leaf blades, while poinsettia is recognizable by the red bracts around its small yellow flowers.
Chinese hibiscus Hibiscus rosa-sinensis
Hibiscus can grow to 4.5 m indoors, while hybrid poinsettia is described as a compact plant under 30 cm.

Frequently asked questions

Are the red parts flowers or leaves?
They are colored bracts; the true flowers are small, yellow, and located in the center of the flower cluster.
When does poinsettia flower?
Flowering usually occurs in December-February, which is when the bright bracts form.
Can I keep it at home if I have a cat?
The plant is mildly toxic to cats and dogs; eating it may cause nausea, vomiting, or diarrhea.
How often should I water it?
Water moderately, and more generously in summer. Reduce watering after flowering.
When should I prune it after flowering?
After flowering, cut the shoots back to 10 cm, then repot about 2 months later.
Taxonomy — GBIF · Native range and toxicity — POWO · Description — Wikipedia and specialist sources · Photos — Unsplash, illustrations — Wikimedia Commons