Add elephant ears -- those large-leaved plants grown from roots the size of softballs, or larger -- to create a tropical flair to home landscapes. Elephant ears are tender perennials, hardy only in the warmest parts of the United States. In areas with colder winters, the plants must be lifted in the fall or replanted every year.
About Elephant Ears
Three genera of plants go by the common name elephant ears: Colocasia, Alocasia and Xanthosoma. The plants are similar in appearance, with large, heart-shaped leaves that grow up to 4 feet or more in length. Of the three types of elephant ears, Colocasia and Alocasia are the most cold hardy, surviving winter temperatures of 15 to 20 degrees Fahrenheit -- in U.S. Department of Agriculture plant Zone 8b. Colocasia is the most commonly found type of elephant ears, since breeders have worked on the species C. esculenta to produce many colorful leaf variations. All three plants have poisonous calcium oxalate crystals in the leaves, stems and roots, so use gloves when handling the plants. Taro is a type of edible elephant ear, but it must be properly prepared before being consumed.
Growing Elephant Ears
In the home landscape, elephant ears do best when planted in partial shade in moist soil. They look best when planted in the back of borders, in large containers or around ponds. Plant them directly outdoors after all danger of frost has passed, or start them indoors six to eight weeks before the last frost date. Cover the roots with 2 to 3 inches of soil and give them plenty of room to spread out. Elephant ears are heavy feeders and need frequent fertilization with either a general purpose fertilizer or a plant food formulated for foliage house plants. The soil around the roots needs to be kept moist, so regular watering is essential, especially for container-grown specimens. Division is best performed in the spring.
Overwintering Elephant Ears
To save elephant ear roots from year to year, cut the foliage back after the first frost, leaving 2 to 4 inches of stem, and carefully dig up the roots. Put the roots in a protected, well-ventilated spot until they're dry to the touch, then store them in vermiculite, packing peanuts or shredded paper. Don't use sand or moss as these materials hold moisture and encourage the roots to sprout prematurely. Keep the roots in a cool, dark location that remains frost-free, such as a crawlspace or basement. Discard any bulbs with soft spots or mold. Plump up shriveled bulbs by spraying them with water a day or two before replanting them in the spring.
Besides the plain green forms, several newer cultivars of elephant ears are available. "Black Magic" grows 3 to 5 feet tall with burgundy-black foliage, while the similarly-sized "Black Stem" has green leaves with burgundy-black veins. "Illustris" is a small elephant ear; its green foliage has black markings and lime green leaf margins and veins. "Lime Zinger" grows 5 to 6 feet tall with bright chartreuse-green foliage.