Odds are you have a poinsettia in your home for the holidays. In the United States, poinsettias are grown in greenhouses and programmed to bloom in time for Christmas. To keep your plant healthy for as long as possible, try to emulate the greenhouse conditions in your own home: bright light and balmy 70 degrees. Keep the soil moist but don’t let the roots sit in water. Make sure the pot has drainage holes. If it is in that decorative foil, either remove the foil or cut the bottom out of the foil so excess water drains out.
After the holidays, grow your poinsettia as if it were a houseplant. With luck, you may be able to see colored bracts (the “flowers”) again next year. Keep the plant in bright light and 70 degree temperature. In the spring, cut the stems back about half the length. Keep indoors or put outdoors in the warm summer months. Apply a houseplant fertilizer and make sure the plant does not dry out. In June, transfer into a slightly bigger pot. In September bring the plant back indoors. To induce flowering, give the plant bright light each day and fourteen hours of uninterrupted dark each night beginning in early October (as in cover with a box or put in a closet). Keep the soil moist but stop fertilizing. The color should form on the bracts in six to eight weeks.