Growing Callas: Ever since Katherine Hepburn whispered, "The Calla Lilies are in bloom again," in one of her old films (Stage Door, 1937), American gardeners have thought of them as special. They are always a romantic favorite, particularly exquisite in arrangements. Callas are native to South Africa, and today they're not only easy to grow, but available in a literal rainbow of colors.

The common white one is Zantesdeschia aethipica, and like all callas, it's hardy in the US only in Zone 7 and above. This means these are "tender bulbs" in most of the country, and have to be lifted and stored in fall. Many people grow callas in patio pots, and the pots can be brought in before frost.

Some gardeners just leave the bulbs in the pots all winter, and then set them out again in spring. Others treat their callas like dahlias, lifting and drying the roots each fall and replanting in spring.

Most of the very colorful callas are a separate species, C. rehmannii, and these have more narrow leaves than the classic white type. If you haven't grown callas, you may be surprised that these bulbs create a sizable plant. Sometimes the clumps grow 36" high. Most all callas have pointed or heart-shaped foliage that's dark green spattered with white spots. The bulbs are irregular, sort of like ginger roots, and several can be planted in the same pot. They enjoy being root-bound. If you plant your bulbs in spring, you'll have flowers in about 65 days.