Peace lilies are generally grown in the ground outdoors only in tropical regions such as Florida or Hawaii; elsewhere, they are grown only as potted plants. If you have potted peace lilies, you can move them outside during the summer months, but once temperatures dip, bring them back inside.
Peace lilies are shade-loving plants in their native habitats, but when grown indoors they need plenty of filtered light, though not direct sunlight. Some varieties can withstand more light than others. Curled, pale leaves generally indicate that the plant is receiving too much light and scorched leaves indicate too much direct sun. In either case, the plant should be moved to a shadier location.
Peace lilies like a rich, loose potting soil containing plenty of organic material. These plants are native to tropical canopy conditions where the soil is rich with deteriorating plant material. Growing them as outdoor garden plants requires soil that mimics this composition.
During the summer, water and mist peace lilies frequently because they thrive with higher humidity, such as that found in the rainforest. In winter, reduce watering but never allow the soil to dry out. If your water is highly chlorinated, use filtered water. Or, you can allow tap water to sit for several days until the chlorine evaporates out.