The eight species of the genus zantedeschia commonly are known as calla lilies. Their beautiful chalice-shaped flowers come in a variety of colors and make an eye-catching landscape plant or cut flower. Zantedeschia usually is planted as a rhizome. Plant large, healthy bulbs in the soil in early spring as soon as outdoor and soil temperatures warm to around 60 degrees Fahrenheit. Once in the ground, the bulb will sprout and flower by late spring.
Difficulty: Moderately Easy
Loosen and turn the soil with a hand tiller to a depth of 8 inches.
Spread 2 inches of peat moss and 1 inch of aged compost over the surface of the soil.
Mix the amendments into the top 8 inches of the soil with a hand tiller, then rake the surface of the soil smooth and walk over it to compact it.
Plant each zantedeschia rhizome so it’s covered by 2 inches of soil and the majority of its "eyes" (as on a potato) face upward. Plant neighboring bulbs 18 inches apart.
Water the soil with a spray from your hose until it’s moist to the bottom of the rhizomes but not soaked. Continue to keep the soil moist to this depth with regular watering until the zantadeschia are in peak bloom. For the rest of the growing season allow the top few inches of soil to dry out before watering.
Different species of zantedeschia have different needs. Zantedeschia aethiopica grows best in partial shade but will tolerate full sun. Other species of zantedeschia need full sun to grow but will tolerate partial shade.