Water the Peace lily when the top inch of soil feels dry to the touch, which is roughly once every five to seven days in warm months. The Peace lily wilts visibly when it is thirsty, and it usually recovers within a few hours of a thorough watering. Reduce watering for the Peace lily in winter to about once every ten to fourteen days, because the plant grows slowly and the soil stays wet longer. Always let excess water drain away, since the Peace lily is prone to root rot if its roots sit in standing water. Use room-temperature water and empty the saucer after watering the Peace lily.
The Peace lily prefers bright, indirect light and tolerates medium to low light better than most flowering houseplants. Keep the Peace lily out of direct midday sun, because hot direct rays can scorch its leaves and leave brown patches. A spot a few feet back from an east- or north-facing window suits the Peace lily well. In very low light the Peace lily will survive but it may stop producing its white flowering spathes. If the Peace lily's leaves look pale or leggy, move it to a brighter location with filtered light.
The cited reference lists Peace lily (Spathiphyllum) as toxic to cats and dogs; ingestion can cause oral irritation, intense burning of the mouth and lips, drooling, vomiting, and difficulty swallowing. These effects come from insoluble calcium oxalate crystals contained in the Peace lily's leaves and stems. If a cat or dog chews or swallows any part of the Peace lily, contact a veterinarian or a pet poison-control line promptly. Keep the Peace lily out of reach of pets and children, and note that the sap can also irritate human skin. The Peace lily is distinct from true lilies of the genus Lilium, but it should still be treated as hazardous to animals.
Plant the Peace lily in a loose, well-draining potting mix rich in organic matter, such as a peat-based mix amended with perlite. Choose a pot with drainage holes, because the Peace lily will not tolerate waterlogged soil. Repot the Peace lily every one to two years in spring, moving it to a container only one size larger. The Peace lily actually flowers more reliably when it is slightly root-bound, so avoid overpotting. Refresh the top layer of soil for the Peace lily each year if a full repot is not needed.
Brown leaf tips on a Peace lily often signal low humidity, mineral buildup from tap water, or over-fertilizing. Yellowing leaves on the Peace lily usually point to overwatering or roots that have been sitting in water too long. If the Peace lily droops dramatically, check the soil first, as both underwatering and severe overwatering can cause wilting. Few or no flowers on the Peace lily commonly mean the light is too low or the plant is too young to bloom. Wipe the broad leaves of the Peace lily occasionally to remove dust and to check for pests such as spider mites and mealybugs.