Common name: Arrowleaf elephant ear, Arrowleaf elephant’s ear, American taro, Tannia, Cocoyam
Arrowleaf elephant ear plants looks very beautiful with their extra-large, elephant ear-like leaves that can cover a large area. The plants are mainly grown for their edible corm which is dark brown, bulgy on one end and thinner on the other.
The plants can grow to a height of 2 meters, without a distinguishable stem. Leaves arise directly from the underground tubers, and grow on petioles that are about 1 meter long. The leaf blade itself is also about 1 meter long with 2 large lobes at the top, and a point bottom end. This gives it the name arrowleaf and elephant ear.
Tender leaves and petioles are used in cooking savory dishes, and can be used only after cooking since they contain an abundance of calcium oxalate crystals, which is toxic to humans. Arrowleaf elephant ear plants also produce flowers which are greenish-white long spadix, covered by a green spathe with curly margins.
These plants are very closely related to Taro or Colocasia esculenta, which is also grown for its edible tubers. The main difference between these 2 plants is how the petiole attaches to the leaves. In Colocasia, the petiole attaches to the leaves at a point near the middle of leaf and not exactly at the margin. Whereas in Xanthosoma, the petiole is attached to the leaf at the margin, the point where the two upper lobes meet.
There is a variant with purple leaves and stem, which is called the Purple taro or Blue taro.
Arrowleaf elephant ear corms are used extensively in cooking; in stews, soups, gravies. They are mashed, fried, boiled, steamed, grilled, baked or even made into flour. It’s a versatile vegetable like Potato, and is used extensively with meats. The high starch content of the vegetable makes it popular in Asian and African countries.
Since Arrowleaf elephant ear plants produce underground tubers, they need rich, porous soil to grow well. When provided with regular watering and good sunlight, the plant can produce tubers within 10-12 months. Arrowleaf elephant ear plants were used to prevent osteoporosis and other bone diseases in traditional herbal medicine.
Propagation is through seeds, suckers or underground tubers. Seed formation is quite rare, and hence vegetative methods of propagation are more popular.