The calla lily plant is an herbaceous, deciduous perennial that prefers a moderately warm, tropical environment. Native to South Africa, the calla lily plant is a cluster plant that produces large green leaves with thick-stemmed trumpet shaped blooms. The calla lily plant, though not a true lily, is relatively easy to maintain but comes with some considerations.
Keep the indoor and outdoor calla lily plants in areas that provide at least six hours of full to partially shaded sunlight. Ensure that full sunlight areas receive mostly morning sunlight to avoid foliage burn. Select a location that provides ample wind protection for outdoor plants.
Maintain a moist environment for the calla lily plant. Water the plant when the soil's surface feels dry. Never allow the calla lily to go without water as it is intolerant to drought periods. Increase the watering schedule during the hot dry summer months. Do not overwater as the plant does not like wet feet.
Fertilize the calla lily plant lightly every two to four weeks from late February through early November. Use a granular fertilizer for outdoor plants incorporating into the surrounding soil. Use liquid applications for indoor calla lily plants. Choose well balanced fertilizers with low levels of nitrogen. Use both the liquid and granular applications at half strength. Never apply the fertilizer directly to the root system as this will cause root burn.
Prepare the calla lily plant for winter dormancy. Cease irrigation and watering of outdoor plants in November. Allow outdoor plants to rest for several days before removing. Gently dig the rhizomes from the planting location. Remove any excess soil from around the system. Rest the rhizomes to dry overnight. Encase the plant in peat moss and store in a dry, dark, cool environment until early spring.
Reduce the watering schedule for indoor calla lily plants in November. Repot the plant once a year. Remove the plant from the container. Remove the excess soil from the rhizomes. Allow the rhizomes to rest. Remove the soil from the container and discard. Thoroughly clean the container or replace with a new one. Repot the indoor calla lily using fresh, nutrient rich soil.