Arisaema costatum
At a glance
- Lifecycle
- Perennial (hardy)
- Exposure
- Full sun
- Frost limit
- −17.8 °C
Cultivation
Prefers a cool peaty soil in the bog, woodland garden or a sheltered border in semi-shade. Plants are nearly hardy in Britain, they normally succeed outdoors in the milder areas of the country. Tubers should be planted about 15cm deep. This species has very large leaves, to 40cm long. Most species in this genus are dioecious, but they are sometimes monoecious and can also change sex from year to year.
Propagation
Seed - best sown as soon as it is ripe in a shady position in a cold frame. When large enough to handle, prick the seedlings out into individual pots and grow them on in light shade in the greenhouse for at least a coupe of years until the corms are more than 20mm in diameter. Plant out into their permanent positions whilst they are dormant. Division of tubers when the plant dies down in late summer.
Edible uses
Root - cooked. It is boiled, dried and then ground into a powder. Some caution is advised, see the notes above on toxicity.
Habitat
Wet cool woodlands and cliffs, often forming large colonies. Shrubberies, 2000 - 2600 metres.
Native range
E. Asia - Himalayas in C. and E. Nepal.