Indoors, place lilies 5 to 7 feet from a south- or west-facing window, and move the plant further away from the window if the leaves become streaked, yellow or brown. True lilies prefer temperatures that range from 50 to 65 degrees Fahrenheit, while peace lilies thrive in temperatures that range from 65 to 80 F. Remove the flower after the lily blooms to prevent seeding, and support tall flowers with a stake.
Place a 4- to 6-inch layer of mulch over the lily before winter, and provide the plant with an organic fertilizer during the spring and summer. After the foliage turns brown in autumn, allow it to remain on the plant to conserve energy. Cut dead stalks back in late autumn or early spring to promote growth the following year.
Water the lily deeply once a week, and maintain slightly moist soil throughout the winter. Use a spray bottle to apply water to the foliage after watering the soil, and provide additional water if the plant appears to droop.
Divide lilies every three to four years, and transplant the plant into a larger container when the soil dries quickly after watering. Plant lily bulbs in autumn, and transplant potted lilies to the garden when the plant's foliage dies.