Elephants ears are tropical plants with showy foliage that range in color from green to almost black. Larger elephant ears can be grown as accent or specimen plants. Smaller varieties can be grown in a mass planting or as a groundcover. Theycan be grown in boggy areas or in pots in shallow water.
Three species of plants are referred to as elephant ears. The foliage of Colocasia spp. and Alocasia spp. is heart shaped, while the foliage of Xanthosoma spp. is more arrow shaped. The stems of Alocasia plants are attached to the leaves at the notch; the stems of Colocasia plants are attached near the center of the leaves. Several varieties were tested in the trial gardens of the University of Tennessee and the University of Georgia to determine the best elephant ears based on growth and resistance to pests and diseases.
Alocasias can be grown outdoors in zones 9 and 10 in partial to full shade in moist soil. In colder climates, they can be grown in containers and moved indoors during the winter. Alternatively, the bulbs can be dug up, kept in a cool dark location in the winter, and replanted in the spring. California a small elephant ear that grows 18 to 24 inches tall. It has rich, green heart-shaped to almost fa- shaped foliage. Frydek has dark green, pointed heart-shaped foliage with ivory veins. The leaves are 1 to 2 feet long and grow on 1 to 2 foot long stems. Nigra grows 3 to 5 feet tall and has dark green to almost black foliage. The 1- to 2-foot wide leaves have a metallic sheen and ruffled edges.
Colocasias are hardier than Alocasias and grow in zones 7B to 10. They can also be grown in containers and overwintered inside, or dug up for the winter and replanted in the spring. They grow best in partial to full shade, although they will grow in full sun if the soil is evenly moist. The heart-shaped leaves of Black Magic are dark purplish-black and grow 12 to 18 inches long on 2- to 3-foot tall stalks. Diamond Head grows 4 feet tall and also has dark purplish-black foliage. The leaves are crinkled 15 inch long hearts. Hawaiian Eye grows 4 feet tall. The foliage emerges black with silver gray veins, and matures to grayish-green with dark purple central eyes. The leaves have a narrow purple border around the edges and bright cranberry undersides. The foliage of Pineapple Princess emerges light green and darkens to iron gray. The 18-inch-long heart-shaped leaves have ruffled sdges and purple veins.
Xanthosomas are hardy only in zone 10, but can be dug up in the winter and replanted in the spring in colder areas. They can also be grown in containers and moved inside during the winter. They grow in sun or shade in evenly moist soil. Lime Zinger has 12- to 18-inch-long leaves on 2- to 3-foot tall stalks. The foliage is chartreuse in the shade and bright yellow in more sun.