Calla Lily Bulbs

Try your hand at growing calla lily plants. These bloomers are a cinch to grow, and in areas where calla lily bulbs aren’t hardy, you can easily store bulbs for winter. To get started planting calla lily bulbs, choose a spot that’s sunny. In hotter regions, like the Deep South or Desert Southwest, choose a site that’s shaded during the hottest part of the day. 

Colorful calla lily flowers (Zantedeschia hybrids) come from bulbs. Typically calla lily bulbs have one side that’s smoother than the other. The side that’s bumpy or has little circular areas produces growing shoots. You might even see calla lily eyes (growing tips) inside the circles. 

How to plant calla lily bulbs isn’t difficult. Plant bulbs so the side with the growing tips faces up. If you can’t detect that side and plant your bulbs upside down, shoots will bend around bulbs and still pop out of soil. Calla lily bulbs are pretty goof-proof. The trickiest part of planting calla lily bulbs is that you must wait until soil is warm and there’s no chance of frost. Calla lilies are tropical plants that crave heat. Air temperatures should be reliably above 55°F at planting time—and beyond. 

Tuck calla lily bulbs 3 to 4 inches deep into soil that’s rich in organic matter and drains well. Grow calla lily plants in containers or in-ground beds. Amend beds with organic matter if you have heavy clay soil. In containers, use a commercial bagged soil-less mix designed for pots. Soil must drain well or you risk having calla lily bulbs rot. This is also why it’s important to plant after soil warms. Calla lily bulbs plus cold, wet soil leads to bulb rot. 
Mulch soil once calla lilies are up and growing to keep roots on the cool side. If you’re growing calla lilies in containers, place other pots around the calla lily pot to shade the container. 

Flowers appear in summer and linger about two weeks. You can cut the blooms for bouquets, but be careful not to get the sap on your skin. After flowers fade, petals shift to darker shades or turn green and close up. This signals the plant is shifting into seed production. Cut off dead blooms to prevent seed formation and let bulbs start building food reserves for next year’s flower show. 

Calla lily plants are hardy in Zones 8 to 9, although gardeners have reported hybrids surviving winters in Zone 6 in protected locations. Outside of Zones 8 and 9, lift bulbs in fall, after leaves yellow and die. In coldest zones, leaves may get frosted and die back. Do not let calla lily bulbs in pots experience a hard freeze. It could damage bulbs.

In late fall in Zones 6 and colder, dig bulbs and dry them. If stems are still attached, they should dry up and fall off. Or use a gentle tug to remove them, but allow the newly exposed spots on bulbs to dry before storing. Do not store moist bulbs; they’ll rot. Store calla lily bulbs in a cool spot for winter. Stash them in a paper bag, or store them in layers in a cardboard box.