How To Grow Calla Lilies

One summer day, my neighbors showed me their calla lilies in full bloom. I had never seen such a large patch. I found out they never dug them up in fall. They didn’t know they should. Yet somehow those calla lilies survived winters in the ground in our cold climate, when they shouldn’t.

I guess my neighbors found a perfect spot, a microclimate within our USDA Plant Hardiness Zone.

What is a Calla Lily?

Calla lilies feature the botanical name Zantedeschia aethiopica. Although their common name is lily, they aren’t related to other types of lilies. Instead, they’re related to jack in the pulpit wildflowers and peace lilies, which also aren’t true lilies.

The flower parts are called a spathe and a spadix. The spathe is the often colorful outer petal, actually a modified leaf structure. The spadix is the upright spike in the center of the spathe. Calla lilies grow wild in the wettest parts of southern Africa.

Types of Calla Lilies

Most available for purchase are hybrids or selected varieties. Flower colors range from white to yellow pink and purple, with several types of variegated leaves, including striped and spotted.

Varieties to consider include:

• Sun Club with bright yellow flowers and lightly spotted foliage;
• Odessa with dark purple flowers;
• African Gold with white flowers and green foliage with gold stripes.

If you can’t decide which color to grow, try several, like those in Tequila Sunrise Calla Lily Mix.

Calla lilies will grow anywhere from one to three-feet wide in the ground. They can form sizable clumps, spreading two to three feet or wider.

Where To Plant Calla Lilies

Calla lilies are hardy in USDA Plant Hardiness Zones 8 through 10. They grow best in moist soil and may go dormant if allowed to dry out.

In warmer climates, Christy Wilhelmi, author of Gardening for Geeks, recommends planting calla lilies on the north side of a house or building where the ground doesn’t dry out as quickly. In other climates, grow calla lilies in full sun to part shade, in the ground or in containers.

Can you grow calla lilies indoors?

Yes! Calla lilies are often sold as indoor plants in bloom, especially around Easter.

If you decide to grow a calla lily indoors, remember it is toxic to dogs and cats, so keep it out of their reach. As with many houseplants, calla lilies grow more slowly in the fall and winter, then pick up again in the spring.

When To Plant Calla Lilies

Because calla lilies don’t tolerate frost, most gardeners plant them once the ground warms in the spring. To give calla lilies a head start, pot them up indoors six to eight weeks before your projected frost-free date, then transplant them into the garden or outdoor containers.

How To Plant Calla Lilies

Calla lilies are easy to plant. The rhizomes, the root structures, are most often sold in early spring.

• Choose big, healthy looking rhizomes.
• Plant one- to two-inches deep in the garden or a container with a potting mix that retains some moisture. Calla lilies don’t mind moisture, which makes them good to plant near ponds or in a rain garden. The “eyes” on the rhizomes, where new growth will emerge, should face up.
• Mulch to keep them from drying out.

How To Care for Calla Lilies

Fertilizing

If you’re growing your calla lilies in containers, fertilize while they’re actively growing and flowering. Use a fertilizer blended for flowering plants with less nitrogen and follow instructions on the label. Calla lilies grown in the ground may not need fertilizing unless the soil requires additional nutrients.

Pruning

Cut back spent blooms to keep your calla lily from forming seeds. This will force the plant to send energy to its roots to grow a bigger rhizome. You can also cut blooms for indoor flower arrangements.

Overwintering

In Zones 8 through 10, calla lilies can be left in the ground year-round. In colder zones, calla lilies will go dormant in the fall.

Before the first frost, cut back your lilies two to three inches above the soil line, then carefully dig up the rhizomes. You should find more rhizomes than you started with. Brush off any soil and let the rhizomes dry off for a week or longer in a warm location with good air circulation. Then store your rhizomes in a cool, dry place, ideally where it’s around 50 degrees.

Check them occasionally for signs of rot. If you find rotting rhizomes, toss them out and start with new, fresh ones in the spring.