To determine if it’s time to water your poinsettia, stick a finger into the soil, advises Goodspeed. If you detect dampness or coldness, leave it alone. You’ll know it’s time to water if the soil is completely dry or if the leaves start to wilt, turn yellow or drop off. Expect to hydrate your plant every 7-10 days, but don’t just pour water. Poinsettias are often sold in foil-wrapped pots to enhance their festive vibe, but this extra layer traps water, which can lead to root rot and kill the plant. Goodspeed suggests removing the foil, placing the potted plant in a sink or tub, spraying it until water runs out of the bottom, then letting it sit for half an hour. or more before re-foiling and returning the plant to its sunny spot. If you live in a drier, very warm home, consider misting the plant regularly as well.