Everyone calls these lilies, but as I understand it, they're not. I could be wrong -- but callas are in the Araceae family, and lilies are in Liliaceae. So I'm not sure why they've been labeled lilies. Maybe someone who actually knows about these things will weigh in on the calla v. lily controversy. Read below the fold...
Contrary to conventional wisdom, callas are not members of the lily family. These South African natives grow from rhizomes, rather than bulbs. Callas are very easy to grow. They do best in zones 7 through 10. In colder climates, dig up the rhizomes and store in a place where they won't freeze, to plant again in the spring. Read below the fold...