Taro (Colocasia esculenta) is a tropical starchy root crop. The large, "elephant-ear" type leaves can grow 2-3 feet long and 1-2 feet wide. Each leaf emerges from an underground corm and the overall plant height can be 5-6 feet.
In addition to the corm, the leaves and stems are also edible. The immature leaves are boiled or steamed and served as greens. The stems are peeled and boiled, and served as a vegetable. They must be cooked to break down the oxalates in the tissues. Varieties with naturally lower levels of oxalates make better cooked greens.
The corms are peeled and baked, boiled or steamed. When cooked and mashed with water, taro becomes poi, a traditional food in Hawaii.
Taro grows best in partial shade, but will grow in full sun if given plenty of water. Best growth is in soils high in organic matter. It will also grow in standing water up to 12 inches deep.
As it grows, multiple smaller plants form around the original corm.
By the end of the growing season, most of these corms, or "eddoes", will be big enough to eat.
Taro is propagated by dividing the clump, and re-planting the smaller corms surrounding the original. These are planted 2-3 inches deep and 2 feet apart.
Taro is perennial in USDA Zones 8-11, but can be grown as an annual elsewhere.
Colocasia esculenta also has many uses in traditional medicines:
Some infections respond to the use of Taro leaves mashed with salt. This poultice can be applied to an injury, covered and wrapped with a large Taro leaf (I wouldn't do this on any open wounds!).
Undiluted poi is sometimes used as a poultice on infected sores. A piece of Taro stem can be touched to the skin to stop surface bleeding. For a sting from an insect, the stem leaf (petiole) can be cut and rubbed on the afflicted area, preventing swelling and pain. (Whistler,W.A. 1992. Polynesian Herbal Medicine.) Note: people with sensitive skin can experience irritation from contact with the sap.
Taro is native to tropical Southeast Asia, but was long ago spread around the world by ancient travelers.
There are similar-looking plants that belong to other genera, other species, or are different cultivars of this species, but the true taro is the only one with peltate leaves (the petiole is attached to the center of the leaf blade).
There are also ornamental varieties of this species that are grown only for the attractive leaves, and are not considered good eating varieties.