To care for a poinsettia, make sure it has adequate water and light. Poinsettias are sensitive to extremes of heat and cold, so keep them in a room with consistent temperatures.
If the poinsettia pot is wrapped, unwrap it as soon as possible so the foliage has room to grow properly. Place indoor poinsettias near a south-, west- or east-facing window for maximum sunlight. Check the soil each day, and if it feels dry, water it. Allow the water to run out of the drainage holes of a potted poinsettia. Do not let the pot sit in water because this prevents air from circulating and damages the roots.
Ideal temperatures for a poinsettia are between 65 and 70 degrees Fahrenheit during the day and between 55 to 60 degrees Fahrenheit at night. Prevent damage to the leaves by not allowing it to touch cold windowpanes. Cold environments also promote root disease in the plant. Poinsettias also do not like drafts of excessive heat, so keep them away from heat registers, fans or radiators.
In February or March, prepare the plant for the following year. Cut the plant back so it is 4 to 6 inches high. Leave between one and three leaves on each stem as new growth comes from the leaf axils.