syn. Z. melanoleuca
Eastern southern Africa.
Sunset zones: 5, 6, 8, 9, 12-24. H1 and H2.
USDA zones: 7-10.
Height: 24 inches (60 cm).
Width: 12 inches (30 cm).
Spring into summer.
White to creamy, 5-inch long spathe surrounding a yellow spadix; followed by a spathe full of berries.
Green, 1 to 1 ½-foot long, arrow-shaped leaves, with transparent oblong spots all over the foliage.
Humus rich, well-drained, slightly acidic soil.
After flowering, apply a low nitrogen/high potash fertilizer. At planting time, toss bone meal or high potash fertilizer into planting hole. Mulch in fall.
Sow seed when ripe.
Divide in spring.
Pests and Diseases:
Soft rot, botrytis, rhizome rot, rust and viruses may be a problem.
Rainy Side Notes
Even when it’s not in bloom, the spotted calla’s almost tropical-looking foliage with its attractive translucent spots is a welcoming site when it returns in spring. In my garden, they have resided in a raised bed of well-drained and mulched soil. They managed to survive a few years of neglect, proving to be a tough survivor in spite of my neglect.
For years I believed that these aroids were not hardy enough; however, Sunset Western Gardening rates it at Sunset zone 5*, with a USDA hardiness rating of zone 6. They might be worth experimenting with a few bulbs in the colder western PNW areas (Sunset zone 4). You can still grow this plant outside its hardiness range by lifting the plants in fall and storing them as you would a dahlia—in a cool, dark place. The following spring, just replant them in the garden.
The common name, calla lily has many believing that Zantedeschias are lilies; however, it is not a lily at all, but a member of the interesting and quirky aroid family, which is comprised of arums and arisaemas, among others. The calla lily’s closest relatives—many that we grow as houseplants—are philodendrons, anthuriums, spathiphyllums, caladiums, dieffenbachias, monstera and aglaonema.
Plant the rhizomes horizontally with eyes facing up, two inches deep and space 8-12 inches apart.
*If you are confused by Sunset and USDA climate zones, Sunset puts out a different rating with most of Western Washington, Oregon and Southern British Columbia are rated zones 4, 5, 6 and 7. Sunset zones take into account the variations or unique weather patterns from cool maritime temperatures, or warmer inland valley temperatures and many other factors. USDA zones only depict the coldest temperatures in their hardiness ratings.
Photographed in author's garden.