Colocasia esculenta is the big green elephant ear seen all over the southeast. The drooping leaves can get 3 feet tall and 2 feet wide, or larger. The mature plant can get 5 to 6 feet tall. The bulbs are usually available in early spring at most nurseries and stores such as WalMart, Lowes, and Home Depot. The bulbs are usually baseball up to softball size. Mine have overwintered here in zone 7 for years.