After Christmas, caring for a poinsettia is relatively straightforward. Keep the plant in a sunny location and water it regularly, but make sure the soil has enough time to dry out between waterings. Fertilize the poinsettia with a balanced fertilizer once a month, but don't overdo it. As the weather warms up, you can move the plant outside to a partially shaded area, but be sure to bring it back inside before the first frost.