The great, white, waxy flowers of calla, also called calla lily, so often seen at florists are nearly weeds in their native South Africa. They're actually perennials in Zones 8, 9, and 10, but since they are not tolerant of frost, they are grown as annuals in other parts of the United States. Gardeners throughout the country can enjoy their lush, green leaves and bright flowers in summer by planting the tuber each spring.
Description of calla lily: Glistening, white flowers grow to 2 feet above the arrowhead-shaped leaves that arise from the rhizome planted below ground. By summer's end, a large clump of leaves displays a more or less continuous succession of flowers.
Growing calla lily: For maximum enjoyment, start rhizomes indoors 8 weeks prior to warm weather. Plant the large tubers in a soil mix high in peat or other organic matter and grow at 70 degrees Fahrenheit. Keep uniformly moist and fertilize weekly with a water-soluble fertilizer. Plant outside in a rich soil high in organic matter that retains moisture. Incorporate a slow-release fertilizer before planting. Grow in full sun for maximum growth. In the fall, lift before frost, drying off foliage and rhizomes. Store in a frost-free place until spring.
Propagating calla lily: Buy rhizomes at garden centers in the spring. Check to make sure they are firm and moist.
Uses for calla lily: Plant callas anywhere you want to achieve a tropical look. They also make dramatic container plants and superb cut flowers.
Calla lily related species: Z. rehmannii is the pink calla, although it shows much variation in spathe color from wine-red to nearly white. It is smaller, growing to 18 inches. Z. elliotiana is a species with white, spotted foliage, and a golden-yellow spathe. The California series of dwarf callas comes in a full range of colors.
Calla lily related varieties: Green Goddess is green with a white throat. White Giant reaches 6 feet and has white flowers and speckled foliage.
Scientific name of calla lily: Zantesdeschia aethiopica