These gracefully shaped flowers are sought after for special occasion bouquets and dramatic shapes in the garden. Though the white and cream-colored varieties are the most popular: perhaps because they were immortalized onscreen by Katherine Hepburn when she said "The calla lilies are in bloom again, such a strange flower, suitable for any occasion" in the film Stage Door. The calla lily's origins are mentioned in both Greek and Roman mythology, with ties to both Hera, goddess of marriage and birth, and Venus, goddess of love and beauty. These flowers are native to the southern part of Africa, specifically Mozambique, South Africa, Lesotho and Swaziland. The plant also grows in other tropical climates, but where it is not native it has become something of an invasive pest, such as in Western Australia. It's not clear when the flowers were first brought to Europe but there is an illustration of them sating back to 1664 depicting the Royal Garden of Paris.
Calla lilies come in a range of colors from white to pale pink to deep burgundy, with some recent hybrids in dramatic colors like bright orange and black. They are a long lasting cut flower and popular for floral arrangements, especially for weddings. They have a faintly sweet and pleasant fragrance. Though they are only hardy for growing in very warm climates (in the U.S. that means southern California, southern Florida and Hawaii), they're widely available as cut flowers or house plants due to their popularity. Calla lilies are not in fact "lilies" at all, that is, not from the lilium family, but are arums, or Araceae. The shape of the flowers has a lily-like appearance, perhaps leading to their misleading nomenclature from a Swedish botanist in the 18th century. Their alluring appearance made them a favorite subject of painter Georgia O'Keefe. These plants can grow up to three feet tall, but there are some newer hybrids which are more compact and remain shorter than two feet tall or shorter.
|Botanical Name||Zantedeschia aethiopica|
|Common Name||Arum lily|
|Plant Type||Herbaceous perennial, rhizome|
|Mature Size||2 to 3 feet|
|Sun Exposure||Indirect sunlight, partial shade|
|Soil Type||Damp, rich|
|Soil pH||Slightly acidic|
|Flower Color||white to pink to maroon and other colors|
|Hardiness Zones||9 to 11|
|Native Areas||Southern Africa, South Africa, Swaziland|
How to Grow Calla Lilies
Calla lilies are easy to grow outside as long as you live in the proper zone. They are grown from a rhizome, not a bulb like Asiatic or Oriental lilies, another key indicator that they are not a true lily. They die back in summer and regrow each year, and the rhizomes should be divided every few years. If you live in a colder zone, say 3 to 7, you may plant calla lilies as an annual. The rhizomes can be dug up and overwintered, but results tend to be inconsistent, and most people in temperate areas buy new rhizomes for the season.
Being a tropical plant, calla lilies thrive in partial shade in places that get hot humid summer weather. Some dappled sunlight is fine, or bright indirect light, but direct sunlight is too strong for the tender petals.
A rich, moist, well-drained soil is best to keep calla lilies blooming. Calla lilies like to grow alongside ponds and can happily tolerate a moist or even wet location.
Don't water too heavily, especially when first planting. Once the rhizomes are established, water once weekly if needed. If there is a drought make sure they stay watered.
Temperature and Humidity
Calla lilies like a fairly warm environment. An 80 degree summer day is perfect for them. They also enjoy humidity and moisture, so humid summers keep the flowers blooming just fine. If temperatures go much below 50, the plants will tend to go dormant. If you want to dig up your rhizomes for overwintering, do this before temperatures go below freezing in your area in the fall.
The growing period for calla lilies indoors is much the same as outdoors, but with the exception that you can grow them in a colder climate. Pot them with a loose, well-draining and rich medium. They need constant moisture as pots will dry out sooner than ground plantings. Keep an eye on them for aphids which can be a problem. You can fertilize during the blooming season to stimulate more flowers: use a basic controlled-release fertilizer. Once the blooms slow down for the season (usually in autumn), water less frequently and allow foliage to die back, removing spent blooms. Let the plant dry out and have a period of rest for a few weeks of dormancy. Then in late winter (February), repot the rhizome in fresh soil, and begin watering to encourage fresh growth.
Calla lilies can be propagated from rhizomes by dividing plants that are growing outdoors. Outside, over time, plants will form large clumps that can be easily divided into smaller units. After several years these divisions will tend to lose vigor, so most people who want to grow them outdoors will invest in new divisions (available from catalogs) or nursery plants.