How to Grow Black Calla Lilies

Calla lilies are not true lilies, but members of the Jack-in-the-pulpit family. They grow in trumpet shapes, with petals that wrap rather than spread, and grow in even more dramatic colors than standard lilies. "Black" callas are actually very deep purple and burgundy, and appear even darker inside the petals and in the shade. These Black Forest or Schwartzwalder calla lilies bring a dark contrast to the garden, and look quite unique, but require the same timing, planting and care as any other calla lily.

Things You'll Need

• Quick-draining soil
• Spade/shovel/garden fork
• Bulb planter

Instructions

1. Prepare to plant calla lilies in fall, around the first frost, in U.S. Department of Agriculture growing zones 8 to 11. This gives the bulbs the winter to grow and establish. Callas bloom from spring to summer, but do best with this cold resting period. In USDA zones 7 and lower, where the winters are more dramatic, plant callas in early spring, before the last frost. This protects them from winter but gives them their cold stratification.

2. Find planting sites where the black callas will get full sun and good drainage. Callas will grow in partial shade, but will not bloom well, and will rot when left in water or wet, thick soil. Make sure that any site has at least 1 foot of space per bulb.

3. Dig into the top 10 inches of soil in sites set 1 foot from each other, and mix 5 inches of quick-draining garden soil in. Callas need loose, airy soil to allow for growth and root development, and won't grow in compacted natural soil. The bulbs hold all the initial nutrition they need, so you don't have to add organic compost or fertilizer at this time.

4. Set bulbs 4 to 6 inches deep in the hole, with noses pointed up, and refill with the soil mix. Water the bulbs with 8 inches of water to wet the entire bulb. Leave the bulbs until they bloom, with minimal watering of only 1 inch a week.

Tips & Warnings

• Once calla lilies begin to grow, they'll need at least 2 inches of water every week.

• Maintain calla lilies with an application of organic compost and 5-10-5 or 5-10-10 fertilizer every spring.

• Calla lily foliage turns yellow and dies after the bloom. Leave the foliage on until it falls to the ground, as it gathers nutrition for the bulbs' future growth during this time.

• In USDA zones 7 and below, dig the calla lily bulbs up at the first frost and store them for the winter to protect them from winter temperatures, then replant them in spring.

References

• University of Illinois Extension; Plant Palette: Calla Lilies; Jennifer Schultz Nelson; April 26, 2009
• University of Minnesota Extension; Yard & Garden Brief: Calla Lilies; Beth R. Jarvis; February 1999
• University of Illinois Extension; Bulbs and More: Planting and Care; Ron Cornwell
• University of Minnesota Extension: Yard & Garden Brief: Spring Flowering Bulbs
• Pacific Callas: Black Forest Callas