Elephant ear, Colocasia esculenta, is grown for its large tropical-looking foliage. Foliage colors include purple-black, green, and white/green variegated. The large heart shaped leaves are produced on 2 to 3 foot long petioles (leaf stalks)
Elephant ear are normally grown from large, round to oval, brown tubers or from rooted plants. The tubers can be placed directly outdoors between 2 and 3 inches deep after the danger of frost has passed (mid-May in central Iowa) or started indoors in large pots in March. Elephant ear performs best in moist soils. Water plants in containers and beds regularly during dry weather. They are also heavy feeders. Apply a slow-release fertilizer to the soil or periodically fertilize with a water soluble product.
Elephant ear thrives in partial shade. It can also be grown in full sun if it is kept consistently moist. Elephant ear can be used as background plants in flower beds and as marginal plants around ponds. Elephant ear can also be grown in large containers.
Colocasia esculenta produces large green leaves that stand 3 to 5 feet tall. Several selections have been introduced onto the market over the past few years. Below are some of the more popular varieties and their descriptions.
- 'Black Magic' - burgundy-black foliage, 3 to 5 feet tall.
- 'Black Stem' - deep green foliage with burgundy-black veins and stems 3 to 5 feet tall.
- 'Chicago Harlequin' - green foliage randomly blotched with lighter green and, 2 to 5 feet tall.
- 'Cranberry Taro' - green foliage with dark stems, 3 to 4 feet tall.
- 'Green Giant' - large green foliage, 3 to 5 feet tall.
- 'Illustris' - green foliage is overlaid with black and has lime green veins and margins, 1 to 3 feet tall.
- 'Lime Zinger' - chartreuse green foliage, 5 to 6 feet tall.
- 'Nancy's Revenge' - dark green foliage with creamy white centers 2 to 5 feet tall.
In Iowa, Elephant Ear will not survive the winter outdoors. The plant must be dug in the fall and stored indoors over winter. Cut the plants back to within 2 to 4 inches of the ground a few days after the first frost. Carefully dig the plants with a spade or potato fork. Allow the base to dry for a day so that they are dry to the touch. Store them in peat moss or vermiculite in the coolest part of the house, typically the basement or a crawlspace. Because of our short growing season, elephant ear may not form large tubers or food reserve in the swollen base to successfully survive the winter in storage. Container grown plants can be overwintered by placing them in a cool porch or basement.
This article originally appeared in the 5/4/2005 issue.