The Spathiphyllum, more commonly known as the Peace Lily, is a houseplant deriving from the Araceae (also called the Arum or Aroid) plant family. A native of the rainforests of Costa Rica, there are few planting zones in the United States that will sustain the plant outdoors. Peace Lilies are typically potted plants best kept inside or within a green house.
Peace Lily Defined
The Peace Lily, according to the North Dakota State University Extension Service's Horticulturist, Ron Smith, is one of the easiest houseplants to maintain. The plant isn't poisonous, but as a member of the Araceae plant family, contains elevated calcium oxalate levels which can irritate the mouth and nasal passages of house pets if chewed or ingested. The Peace Lily is a dark green, leafy plant that produces white flowers. The tropical plant is related to the Calla lily, Anthurium and Chinese Evergreen, which are also members of the Araceae plant family.
Peace Lily Care Requirements
Due to the Peace Lily's tropical nature it must be maintained within a temperature of between 20 to 29.4 degrees Celsius. The Garden Helper website warns against allowing the plant to experience temperatures lower than 4.44 degrees Celsius. The houseplant is comfortable in the artificial lighting offered by most electric lights in a house, but prefers sunlight in a sunny window protected by a sheer curtain. When it comes to watering and fertilising the Peace Lily, care is minimal. Water the plant about once a week without over watering. The Flower Shop Network warns against allowing the Peace Lily's pot to sit in a water-filled saucer. Under watering will result in wilting, yellowing or browning of the leaves or death. Fertilise the plant with plant fertiliser every month during the spring and summer months. The Peace Lily should be repotted about every two years to keep it from becoming root bound.
The Peace Lily can be placed outdoors in the summer if your temperatures stay above 15.6 degrees Celsius. It is important to know your planting zone if you intend to place the plant outdoors during the summer months. The North Dakota State University Extension Service recommends bringing in the plant at night if the temperature drops to 10 degrees Celsius or lower. NDSU also suggests placing the plant under a shade tree or on the north side of your home to filter the bright sunlight that is much brighter than the interior light to which the plant is accustomed. If you don't know the average temperatures for your planting zone, consult the USDA Hardiness Zone Finder offered by the National Gardening Association (See Resources).
Sustainability of an Outdoor Peace Lily
Unless your area's outdoor conditions mimic those of the rainforests in Costa Rica, your Peace Lily is a houseplant and should be treated as such. Peace Lilies require fertilised soil and maintaining the balance of nutrients found in potting soil fertilised with plant fertiliser is hard to sustain when planted outdoors. Summer outdoor exposure for the plant is fine if your temperatures allow for it, but as a long-term, permanent outdoor plant, the Peace Lily will not thrive and may not even survive.