While most gardeners grow calla lilies from bulbs, the plants can be started from the seeds the plant produces. The process of growing calla lilies from seed involves germinating the seeds outside the soil in an ideal, controlled environment, according to the Calla Lily Guide website. From seed to blooming plant takes about 3 years.
Select ripe seedpods from the plant for propagation. Locate the seedpods directly behind the flowers. Calla lily seedpods turn yellow and become soft when ripe. Break the pods open and wash away the pulpy material within the pods.
Start the seeds in a damp paper towel. Place the seeds between two pieces of toweling. Keep the towel moist, but not wet, as wet toweling may cause seed rot, for two to three days. Check for growth and discard seeds that have not germinated.
Transplant the seedlings into small pots. Gently place two germinated seeds about a ½-inch deep in pots filled with commercial potting soil. Keep the soil most rather than wet to avoid rotting during this growth phase. Keep the soil temperature around 75 degrees and water with warm water to avoid shocking the seeds.
Transplant the seedlings from the small pots into larger permanent pots or the garden when the plants are large enough to tolerate the larger space. Remove and discard week plants at this time.