What is a poinsettia?
The poinsettia (Euphorbia pulcherrima) is a woody shrub native to Mexico and Central America, where it grows up to 10 feet tall along forest edges. Indoors it is kept compact — typically 1–3 feet — and is most recognisable for the vivid red, pink, white, or marbled “petals” that appear in winter. Those coloured structures are not petals at all: they are modified leaves called bracts that surround the tiny yellow true flowers (cyathia) at the centre. Poinsettias belong to the spurge family (Euphorbiaceae) and share the genus’s characteristic milky latex sap.
How much light does a poinsettia need?
Poinsettias need bright, indirect light — at least six hours a day. A spot a few feet back from a south- or east-facing window is ideal. Too little light causes pale foliage, leggy stems, and poor bract development; harsh direct afternoon sun scorches the bracts and the softer leaves. During the holiday display period, consistent light (and consistent darkness — see below) matters more than intensity, so resist the urge to shuffle the plant around.
How do you water a poinsettia correctly?
Water when the top inch of soil is dry — roughly every five to seven days in typical indoor conditions. Soggy soil is the number-one killer: the roots rot quickly in waterlogged compost, and the first symptom is often wilting even though the pot still feels heavy. Use a well-draining potting mix, a pot with drainage holes, and always discard any water that collects in the saucer within half an hour of watering. In summer, when the plant is actively growing, it may need water slightly more often.
How do you get a poinsettia to rebloom?
Poinsettias are obligate short-day plants — bract colouration is triggered by long, unbroken nights. Starting around mid-September, give the plant 14 hours of complete darkness each night (a cardboard box, a closet, or a dark spare room all work) and 10 hours of bright light each day. Even a small amount of stray light during the dark period resets the clock. Keep night temperatures between 60 and 65 °F. Continue the regime for 8–10 weeks and you should have coloured bracts by late November or December.
Why are my poinsettia’s leaves dropping?
Leaf drop is almost always a stress response. The most common triggers are cold drafts from windows or exterior doors, sudden temperature swings, being moved from a bright shop to a dimmer home, or overwatering. When you bring a new plant home, find a stable spot away from vents and drafts and leave it there. A small amount of lower-leaf drop in the first week is normal acclimatisation; ongoing drop points to a cultural problem worth investigating.
Is a poinsettia toxic to pets and children?
Poinsettia has a mildly toxic reputation that is frequently overstated. The milky latex sap contains diterpenoid euphorbol esters and saponin-like compounds that can cause mild irritation to the mouth and gastrointestinal tract — drooling, vomiting, or a temporary skin rash if the sap contacts bare skin. The ASPCA classifies it as mildly toxic to cats and dogs. Serious or life-threatening poisoning from poinsettia is extremely uncommon, but the plant is still best kept out of reach of cats, dogs, and young children as a sensible precaution.