These impressive ornamental specimens grow outside in sheltered location in USDA zones 8 through 11. Colocasia is a swamp plant that develops a hardy root system under the water. For this reason, elephant ears make great landscape plants in, around, or near water features in the garden. In the chillier northern areas, elephant ear is treated as an annual wherein the bulbs or tubers of the plant are dug up and stored through the winter and then replanted in the spring. The plant itself reaches heights of between 3 and 5 feet (1-1.5 m.) tall and for this reason is usually grown as an outdoor specimen, however, it is possible to grow elephant ears indoors.
How to Grow Elephant Ears Indoors
When growing Colocasia inside, be sure to choose a fairly large container to pot the plant in. Colocasia can attain a good size, so you will want to be prepared. Choose a site to situate the indoor elephant ear plant that is in indirect sunlight. Colocasia can tolerate direct sun, but it will tend to sunburn although it may acclimate after a time; it will really do much better in indirect sun. Growing Colocasia inside requires high humidity. Use a humidifier in the room where you plan on growing Colocasia inside. Also, elephant ear houseplants should be elevated slightly with a layer of rocks or pebbles between the pot and the saucer. This will increase the level of humidity surrounding the indoor elephant ear plant while preventing the roots from coming into contact with the water, which may cause root rot. Soil choice for growing Colocasia inside is a well-draining, peat-rich medium. Temperatures for your elephant ear houseplants should be between 65 and 75 degrees F. (18-24 C.).
Houseplant Care of Colocasia
A fertilization regime every two weeks with a 50 percent diluted 20-10-10 food is an integral part of houseplant care of Colocasia. You may discontinue the fertilization during the winter months to allow the Colocasia to rest. Also, cut back on watering during this time and allow the soil to dry out slightly. Pots with tubers may be stored in the basement or garage with temps between 45 and 55 degrees F. (7-13 C.) until the spring growing season and once temperatures have warmed. At that time, propagation via tuber root division may occur. Flowering of the indoor elephant plant is rare, although when grown outdoors, the plant may bear a small green sheathed yellow-green cone of flowers.
Colocasia Varieties
The following varieties of elephant ear make good choices for growing indoors:
‘Black Magic’ a 3 to 5 foot (1-1.5 m.) specimen with dark burgundy-black leaves. ‘Black Stem’ which as its name suggests has black stems with burgundy-black veins on green foliage. ‘Chicago Harlequin’ grows 2 to 5 feet (61 cm. to 1.5 m.) tall with light/dark green foliage. ‘Cranberry Taro’ has dark stems and grows 3 to 4 feet (1 m.) high. ‘Green Giant’ has very large green foliage and may get as tall as 5 feet (1.5 m.). ‘Illustris’ has green foliage marked with black and lime green and is a shorter varietal at 1 to 3 feet (31-91 cm.). ‘Lime Zinger’ has lovely chartreuse leaves and is quite tall at 5 to 6 feet (1.5-2 m.). ‘Nancy’s Revenge’ is of medium height at 2 to 5 feet (61 cm. to 1.5 m.) tall with dark green leaves with creamy centers.
