Plants

• Most elephant ear plants are specific varieties of Alocasia macrorrhizos, Colocasia esculenta and similar species, though plants in the closely related Caladium and Xanthoma plant clans are also sometimes known as elephant ears. Tropical-looking foliage comes in green, green with white variegated and purple-black variations; some varieties feature highly textured and patterned leaves. Most types do well in partial shade, but some will also thrive in full sun if they are given sufficient water. All plants require moist soils -- even wet soils -- especially during hot weather. Most varieties are hardy to Zone 7, but can be grown in colder climates if you dig up corms before winter or grow plants in containers.
  
  

Corms

• Herbaceous perennials, elephant ears grow from large underground bulb-like corms that are planted outdoors in spring after all danger of frost has passed. They grow successfully in large containers also -- though consider the maximum size of the plant and corm when choosing suitable container varieties. Bulb-like corms store plant energy during dormancy and reflect the relative size of the elephant ear plant, though as the plant increases in size, this storage root also grows larger. The corm -- sometimes called a "mammy" -- looks something like a top, features ridges, lumps and roots and is brown with pink or white flesh. Most corms weigh 1 or 2 lbs., but depending on the species and variety, some can get as big as a football and weigh up to 8 or 9 lbs. Separate cormlets or "daughter bulbs" from the main corm to start new plants.
  
  

Types

• Size of elephant ear plants and corms is largely determined by variety, or plant genetics, which will determine general size range, color, shape and other features. Elephant ear varieties that are fairly easy to find include Black Magic, which produces 2-foot-long purple-black leaves atop 3- to 4-foot leaf stalks; similarly sized Black Stem, with deep green foliage with burgundy-black stalks and leaf veins; and smaller Illustris, with purple-black leaves but lime green veins that seem to glow. Ruffles grows to 6 feet and has dark green foliage with scalloped edges. Also quite tall is Lime Zinger, with chartreuse foliage. A true giant is 9-foot-tall Jack's Giant, which features huge green leaves with pale green veins.
  
  

Nutrition

• Size of plants and corms also depends on proper nutrition, and elephant ear plants are heavy feeders. Enrich your soil with several inches of rich compost or well-rotted manure, working it into the top 6 inches of soil before planting in spring, so there will be a constant supply of nutrients as this organic matter breaks down. Also work slow-release fertilizers into the soil at planting, and water monthly with water-soluble fertilizer.
  
  

Climate

• Size of elephant ear corms and plants also depends on climate. Plants grow largest where the growing season is long and temperatures are warm to hot -- such as Florida, where elephant ears have escaped cultivation and become invasive species. Farther north, where the growing season is shorter, plant size is limited. Several days after the first frost, cut tops back to 2 to 4 inches, dig corms, dry them and store them indoors in peat moss in the basement or other cool dark place for the winter. Elephant ears grown in containers can be overwintered in their pots.