Family: Araceae

Originating from tropical Asia, the name was adapted from colocasia, or taro, the well-known tropical food. Alocasias have spectacular arrow-shaped foliage, sometimes silvery in colour, with prominent green veins. They make superb indoor plants. The sap may cause problems for people with sensitive skin. They are known by various common names, including elephant's ears.

Species

A. x argyraea has dark green leaves with a silver sheen and shiny reddish brown undersides. It grows to 60 cm (24 in).

A. cuprea, giant caladium, has 45 cm (18 in) long leaves which are purple on the underneath and dark green on top.

A. macrorrhiza, giant taro, is cultivated in many tropical countries for its edible rhizome and shoots. It can grow to over 4 m (13 ft) tall in tropical zones. It has a wide natural distribution from India, through Malaysia, and across to Papua New Guinea and northern Australia.

A. odora, sweet alocasia, has fragrant flowers, similar to a greenish calla lily, and large, deep green, arrow-shaped leaves. It grows to a height of 1 m (3 ft).

A. zebrina grows to over 1 m (3 ft), with 20-30 cm (8-12 in) leaves on long stalks and zebra-like markings in pale green and black.

Cultivation

Outside the tropics, alocasias are grown in a warm humid greenhouse or conservatory. Grow them in pots of humus-rich compost and provide medium light levels. Outdoors grow in a shady spot in humus-rich but well-drained soil. Propagate by division in spring.

Climate

Warm subtropics to tropics.