Do Calla Lily Bulbs Multiply?

Growing Calla Lily

• Plant the odd-looking, misshaped calla lily rhizomes, or tubers, in the spring after the threat of frost passes. Each rhizome produces between 10 and 30 flowers throughout the growing season. Plant calla lily rhizomes shallow, with the rhizome just under the soil surface. The rhizomes have bumps or eyes like a potato indicating a flower will grow from the eye. Plant the rhizome so that as many of the eyes as possible are facing up. Calla lilies prefer sun or strong, bright light and consistently moist, but not soggy, soil. As the calla lily blooms, harvest the flowers for fresh cut flower arrangements, but leave the leaf foliage on the plant until it naturally browns and dies at the end of the season in the fall.

Calla Lily Rhizome

• The calla lily rhizome is an inflated root where new plant shoot buds develop and grow. Rhizomes grow horizontally just beneath the soil surface and are fed by the plant's foliage, which sends food and energy to the developing rhizomes. During the growing season, as the mother rhizome receives the food and energy from the foliage above, it begins forming new, tiny rhizomes attached to the mother. At the end of the growing season when the calla lily foliage has naturally browned and died, the new, attached rhizomes have their own shoot buds and stored energy to produce a new, separate calla lily plant the following season.

Harvesting New Rhizomes

• In the fall before the first frost or after the calla lily foliage dies, carefully dig up the rhizome. Brush off any soil clots from the rhizome, so that you can easily see the new rhizomes growing from the mother. The multiple new rhizomes on the main rhizome should easily break off by using your fingers. If one or more of the new rhizomes does not easily break off, it is not ready for harvesting and should be left on the mother rhizome. After separating the new rhizomes from the main one, allow all of the rhizomes to dry about one week to heal any wounds at the breaks before storing the rhizomes for the winter.

Planting New Rhizomes

• In the spring after the threat of frost passes, plant the new, harvested calla lily in the same manner you planted the original rhizome. Select a sunny location with rich, loamy, well-draining soil. Make sure the eyes, or shoot buds, point up toward the surface. Space the rhizomes 10 inches apart allowing the plants to spread and grow. In 2 or 3 years, harvest more of the multiplying calla lily rhizomes from the established mother.