The peace lily requires relatively little light and thrives in normal household conditions, making it a favorite for offices and homes with low light conditions. Its lush green foliage and unusual blooms make this plant a conversation piece. When provided with adequate water and occasional fertilizer, the peace lily lives for years in the home, but does require routine repotting when the plant outgrows the original container. Repot in the spring when growth is minimal.
Select a new plant pot that is one size larger than the current pot. Plant pot sizes are measured by the diameter of the top of the pot--which also equals the height of a standard plant pot--and are sold in increments of 2 inches. Sizes typically range from 2 inches to 14 inches and then go to 17 and 21 inches. If your current pot is a 6-inch pot, choose an 8-inch pot.
Fill the new pot half to three-fourths of the way with fresh potting soil. According to Washington State University Cooperative Extension, tropical houseplants prefer a potting medium with a higher amount of organic matter than typically provided in commercial potting soil. Mix one part peat moss to one part potting soil to create soil for peace lilies.
Place one hand over the top of the original pot so the stems of the peace lily rests between your fingers and the rim of the plant pot rests on your hand. Invert the pot, resting the weight of the pot on your hand. Tap the bottom of the pot to loosen the soil and slide the plant free.
Loosen the roots with your hands if they tightly coiled. Use care not to break or damage young hair roots. Remove loose soil around the roots.
Position your peace lily in the new pot so it rests at the original planting depth. Spread the roots over the soil. Fill in around the roots with fresh soil. Fill the pot with soil to within 2 inches of the rim. Firm the soil down with your hands to secure the plant.
Water thoroughly until water runs free of the bottom of the pot. Place the repotted peace lily in similar lighting as the original. Water when soil dries, but do not fertilize the plant for three to four weeks. Resume normal care.