Colocasia affinis jenningsii: Elephant Ears, Taro
Those who are interested in useful tropical and subtropical plants will doubtless know at least the name of this genus for Colocasia esculenta (syn. C. antiquorum), or taro, is one of the most important edible plants of Asia and Africa. The tubers contain a large amount of starch and are the source of poi. Particularly well-known for this are the colocasias from Java, Fiji and Hawaii.
The species grows wild in the East Indies by the edge of lowland swamps. The stems are up to 30 cm (1 ft) long, the leaves usually 15 cm (6 in) long and about 10 cm (4 in) across. The root is a small undergroundwhich serves as a storage organ.
Of all the colocasias the one is perhaps the most delicate but at the same time also the most beautiful. It is well suited to growing in a paludarium in a warm and light room that is not often aired. The ideal place for it is a well-lit aquaterrarium or a glass plant-case, where it must be put in a shallow dish kept permanently filled with water. It is important that it is provided not only with a constant and fairly high temperature but also with constantly high atmospheric moisture, for the leaf margins quickly dry out if the humidity decreases for even a few days.
Much hardier is the previously mentioned C. esculenta, which can grow to a height of as much as 1 m (3 ft). The leaves are shield-shaped, up to 70 cm (28 in) long, with a sinuate margin. Similar, and equally large is C. indica, which differs by having pronounced veins. Only somewhat larger than the species is C. fallax with velvety leaves that have a metallic blue sheen.
All colocasias should be grown in warm, moist conditions in a peaty compost with a small addition of sand and loam. They must be fed frequently throughout the growing period. Some species drop some of their leaves in winter, the same as alocasias. They are readily propagated by cutting up the tuberous roots or by seeds, which germinate rapidly.