When to plant:
Any time between February and June (but after danger of frost is past) bury them 3 to 4 inches deep in porous soil directly in the garden or in containers.
Give them water when the soil is slightly dry (but don't overdose — the hybrid callas dislike soggy soil), and they're good to go.
Eight weeks after planting, flower stalks begin shooting up, and you'll be delighted by blossoms for the next couple of months.
Although Z. aethiopica has been known to soldier on in Zones 8-10, its colorful relatives are more comfortable in Zones 9 and warmer. Or treat them as tender perennials in colder climates.
Callas bask in anything from full sun to partial shade — bright, indirect light being ideal. Dense shade might put a damper on bud count, and scorching midday summer sun can prove equally challenging.
The color-soaked hybrids prefer a well-drained, porous soil. Sandy soils are simpatico if you add fertilizer; clay soils can be tricky. Excessive nitrogen will encourage a bounty of leaves and long stems, squelching bud production. In a fertile soil, no further food is needed.
Before frost threatens in autumn or early winter, whisk them indoors to rest the tubers after their labors. If calla lilies are planted directly in beds, dig the tubers from the garden or store them in their pots in a dry 55ºF environment, withholding water for eight weeks or longer before jump-starting the cycle again with light and water.
Plant with dahlias and gladiolus for a cutting garden that will last until frost.
Calla lilies are dangerous to pets if any part of the plant is ingested.