Daniel Gill, Merrill, Thomas A. | 1/31/2006 2:15:27 AM
By Dan Gill
LSU AgCenter Horticulturist
Some plants have public relations problems through no fault of their own. The worst situation exists when a plant becomes associated with an event that is sad or distressing. For example, the lovely calla lily has almost become a cliché for funerals.
I was reminded of this recently when I recommended calla lilies as the perfect plant for a spot in a friend’s landscape. The immediate response was, "Isn’t that the flower used in funerals?" When I answered yes, he asked for another suggestion.
The ironic part is when was the last time you saw callas at a funeral? The connection is so ingrained in our culture, however, that this delightful flower often doesn’t stand a chance when it’s suggested for a garden. So I’ve decided it’s time to do a bit of work to change the image of a plant that deserves to be used more often in our landscapes.
The common calla lily (Zantedeschia aethiopica) is native to South Africa and grows from a tuber.
The plants are robust and tropical looking with glossy, large, arrowhead-shaped leaves that are a rich green. Its foliage grows to be 2-feet to 3-feet high on thick petioles (leaf stems) that originate at or near ground level. The elegant flowers, produced singly on 2-foot to 3-foot stems, are funnel shaped and creamy white and have a yellow columnar structure sticking up from the center. They last a week or more when cut and placed in water.
Although most people think of the larger white ones as the flowers, the actual flowers are very tiny and are located on the column, which botanically is known as a spadix. The showy white structure is a modified leaf called the spathe.
This flower structure is common among plants in the Araceae family – to which the calla lily belongs. Other well known members of the family include the anthurium, peace lily (Spathiphyllum), dieffenbachia and Jack-in-the-pulpit (Arisaema triphyllum).
The growth cycle of the calla lily is much like our native Louisiana irises, and many aspects of its culture are similar. Like the Louisiana iris, established calla lilies begin active growth in the fall garden as the days shorten and temperatures begin to cool – generally in October. The foliage continues to grow over the winter, and the amount of growth depends on the severity of the winter.
After a mild winter, the growth is well up by February, and blooming is not far off. Colder winters with hard freezes will slow or nip back the growth and delay blooming until late spring or early summer.
Fall is the best time to plant dormant tubers, but tubers often don’t become available in the nurseries until early spring. Fortunately, tubers can be planted in late winter or early spring and still produce good results.
Flowering begins in March and generally continues until late April or early May. During that time, a succession of flowers is produced, and one to three of them are typically open at a time. Callas do not cover themselves with flowers. But even though they may not bloom prolifically, it only takes a few of the graceful white flowers against the dark green foliage to create quite a show.
As temperatures begin to rise in May, callas will stop growing and blooming. Through the hot summer months the foliage will gradually turn yellow and brown. Don’t panic – this is normal! Unattractive leaves should be pruned off as they occur. Then by late summer the plants are semi-dormant with few, if any, leaves. Since they are not in active growth, August and September are excellent times to move or divide calla lilies.
If you would like to plant some calla lily tubers into your garden now, choose a location that gets four hours to six hours of sun each day. Morning sun and afternoon shade are ideal. Although calla lilies will grow in full sun, the foliage often loses its rich green color and tends to look yellowish. Deep shade, on the other hand, will limit flower production.
Callas are heavy feeders, and the tubers should be planted in rich soil amended with generous amounts of compost or rotted manure and a little general-purpose fertilizer. Plant the tubers an inch below the surface of soil. If you are planting more than one tuber, space them about 12 inches to 18 inches apart and cover the soil with a couple of inches of mulch to suppress weeds and conserve soil moisture.
Adequate moisture is critical to success with these plants, and you must keep them well watered during their growing season. The good news is that this generally is not a huge chore during our normally wet winters.
Callas are excellent plants for poorly drained areas that tend to stay wet. They will even thrive in containers set into a pond or aquatic garden – just like Louisiana irises. Grown in an aquatic situation, the foliage tends to stay greener through the summer.
Fertilize established plants growing in your garden with an all-purpose granular fertilizer in February. Fertilize plants in aquatic gardens with fertilizer tablets formulated for use on pond plants in containers (available at nurseries that carry aquatic gardening supplies) following label directions.
Dramatic clumps of calla lilies are a wonderful addition to the landscape. Use them to accent partly shady areas, and if anybody asks about funerals, well, just smile.
Get It Growing is a weekly feature on home lawn and garden topics prepared by experts in the LSU AgCenter. For more information on such topics, contact your parish LSU AgCenter Extension office or visit our Web site at www.lsuagcenter.com. A wide range of publications and a variety of other resources are available.