Native to South Africa, Zantedeschia (Calla Lilies) have become popular garden or household plants. Mainly grown for their magnificent, chalice-shaped flowers (spathe) surrounding a yellow finger-like stalk (spadix), and their arrow-shaped, spotted leaves, they are not true lilies, but are arum (Jack-in-the-pulpit) family members. Whether used in borders, containers or as cut flowers, they always provide a spectacular effect with their rich, cheerful colors.
Zantedeschia species are perennials in tropical and subtropical areas, and some species remain evergreen year-round provided they are given adequate moisture at all times. There are 2 main types of Zantedeschia:
Hardy Zantedeschia (Zantedeschia aethiopica) or Arum Lilies
- They generally display pure white flowers and can survive in hardiness zones 7 or 8. They can easily tolerate freezing temperatures. Although the foliage of these plants will die back during the winter, they will survive and will emerge in the spring as if nothing had happened. However, applying an ample layer of mulch in the fall would help get these plants through winter.
Tender Zantedeschias or Calla Lilies
- They feature amazing flowers in almost all the colors of the rainbow and generally white-speckled leaves. Main cultivars include Zantedeschia elliotiana (golden yellow), Zantedeschia rehmannii (pink), Zantedeschia albomaculata (white), Zantedeschia jucunda. Calla Lilies are generally hardy in zones 8-10.
- In cooler climates (zones 3-7), the tubers are planted in the spring, after the danger of frost has passed, and usually treated as annuals. However, if you want to save your bulbs for next spring, you may dig them up before the first frost and store them over winter before replanting them next spring. Not sure about your growing zone? Check here.
- Calla lilies range in color from pure white to a deep dark purple verging on black. In between are the colors typical of a sizzling summer: from golden yellow to all the colors in a dazzling sunset such as deep orange, burgundy red or even hot pink!
- The flowers of calla lilies attract so much attention that you could almost ignore their leaves. This would be a shame, however, since some of them feature uniquely speckled leaves. They look as if someone blithely spattered a paintbrush full of white paint over them.
- Zantedeschia are well-suited for bog or marsh gardens, for planting near ponds and streams, as border plants or for containers. Some, e.g. Zantedeschia aethiopica, can be grown in water up to 12 in. deep (30 cm).
- Zantedeschia makes excellent cut flowers and have one of the longest vase life among cut flowers (up to 2 weeks). They are gorgeous in wedding bouquets and fresh floral arrangements. If you’d like to pick a flower to put in a vase, remember not to cut it with a knife. Instead, carefully pull the flower stem out of the plant.
- Zantedeschia grow in full sun or partial shade. Full sun is best in cool summer areas but part shade is preferred in hot summer areas. They perform best in organically rich, moist, well-drained soils. Consistent moisture is essential.
- Calla rhizomes should be planted in spring. They may be started indoors as early as a month before the average last frost date (for earlier blooms) or planted directly in the ground after the danger of frost has passed.
- After planting, it may take 2 weeks or more for the first shoots to appear. The rhizomes take about 13-16 weeks to start flowering depending upon the cultivar and planting date. When Calla Lilies are planted in the spring, they will produce flowers between midsummer and early fall for 3-8 weeks. Their flowering period depends on the temperature, amount of light and the variety. In climates where Calla Lilies are perennial, they typically bloom in late spring to early summer.
- Propagate by division, in spring. Small rhizomes that have been overwintered in pots under cover can be cut up into sections, each with a visible bud. Large overwintered clumps in the garden can be divided by lifting the plant before there is much top growth, and chopping through the roots with a spade and dividing into smaller sections.
- Zantedeschia can suffer from cold damage, but are otherwise fairly trouble-free.