Dieffenbachia, sometimes called dumbcane, is a tropical plant from the family Araceae often grown as a houseplant. It is hardy in U.S. Department of Agriculture plant hardiness zones 10b through 11, so you can grow it outside if you live in a warm climate. The plant's leaves are variegated -- marked with different colors. It's called dumbcane because it contains a substance that causes stinging and burning to the mouth if ingested, resulting in difficulty with speech. It can be poisonous to children and pets, so keep them away from dieffenbachia plants. Many people like dieffenbachia, however, because it's a hardy plant and also because it comes in several different varieties.
"Rudolf Roehrs" (Dieffenbachia maculata) is also known as spotted dumbcane because its creamy leaves have white spots. The center and edges are green. When planted outside, this variety grows to be 4 to 6 feet tall, but if you're growing it as a houseplant, it can be cut back so it won't get too big. Its leaves will grow to be 10 to 12 inches long.
Another cultivar of Dieffenbachia maculata, "Camille," is a lush, bushy plant with pale yellow leaves and bright green margins. It can grow to be about 3 feet tall, and its leaves will grow to almost 16 inches long.
The Dieffenbachia maculata cultivar "Compacta" is similar to "Camille," and has leaves with creamy centers and green margins. As the name implies, the plant is compact and full in appearance. It can also grow to be quite large, up to 3 feet tall.
"Tropic Snow" (Dieffenbachia amoena) has green leaves with white along the veins and deep green margins. Like the "Compacta," its stem is barely visible because the leaves grow so densely. The leaves are smaller, about 12 inches long. "Tropic Snow" does well with little light.
The cultivar "Sparkles" features brightly colored leaves with light and bright green variagation and a white rib. It's smaller than some varieties, with leaves 7 to 8 inches long and 4 to 5 inches wide. "Sparkles" is a compact plant with smooth, erect leaf growth.
Other varieties include dieffenbachia "Exotica" (Arvida), with ivory leaves and lots of small green spots; "Hilo," which has large, pointed leaves and white veins; "Paradise," with creamy yellow leaves and green speckles; "Snow Queen," with soft yellow or gold leaves, dark green margins and white veins; and "Tiki," a large plant with silver leaves and green and white spots.