Arisaema
Arisaema tortuosum
Family: Araceae
What it is like
Arisaema tortuosum is a PERENNIAL growing to 0.6 m (2ft) by 0.3 m (1ft in). See above for USDA hardiness. It is hardy to UK zone 7. It is in flower from May to June. The species is monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and is pollinated by Flies. The plant is not self-fertile. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It prefers moist soil.
Height (m): 0.6
Where it is found
Forests, shrubberies and open slopes to 3000 metres. Moist shady places at elevations of 1500 - 2200 metres in Nepal.
E. Asia - Himalayas from Simla to Sikkim and Bhutan.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Tuber - it must be thoroughly dried or cooked before being eaten. The tubers are boiled and eaten in Nepal, mixed with lime juice (Citrus aurantifolia) or another sour substance. The tubers are buried in masses in pits until acetous fermentation takes place, they are then dug up, washed and cooked, by which means their acrimonious principles are in part dispersed. However, violent illness has still been known to follow a hearty meal of the tubers. See also the notes above on toxicity.
Root: includes bulbs, corms, tubers, rhizomes etc.
Medicine
Rating: 2
The roots have been used as a vermifuge in cattle. The juice of the tubers is applied to the wounds of cattle in order to kill any parasites. The dried powdered tubers is applied to snake bites. The seeds have been mixed with salt and used to treat colic in sheep.
Vermifuge: Expels and kills internal parasites.
Other
Rating:
The tubers have insecicidal properties.
Insecticide: Kills insects.
How it is grown
Prefers a cool peaty soil in the bog garden, woodland garden or a sheltered border in semi-shade. Prefers a loamy or peaty soil and will tolerate a sunny position if the soil is moist but not water-logged and the position is not too hot or exposed. Plants are not very hardy outdoors in Britain and are normally best if given protection. However, they can succeed outdoors in the milder areas of the country if the tubers are planted about 20cm deep. Plants require protection from slugs. Most species in this genus are dioecious, but they are sometimes monoecious and can also change sex from year to year. This species usually bears either monoecious or all male flowers.
Propagating it: Seed - best sown as soon as it is ripe in a shady position in a cold frame. Stored seed remains viable for at least a year and can be sown in spring in the greenhouse but it will probably require a period of cold stratification. Germination usually takes place in 1 - 6 months at 15°c. 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.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; not Deep Shade;
Habit: Perennial
Hardiness: 6-9
Growth:
Soil: Light (sandy), medium
Shade: Full shade, semi-shade, no shade
Moisture: Moist
Things to keep in mind
The plant contains calcium oxylate crystals. These cause an extremely unpleasant sensation similar to needles being stuck into the mouth and tongue if they are eaten but they are easily neutralized by thoroughly drying or cooking the plant or by steeping it in water.
Its other names
Local names
Synonyms
A. curvatum. (Roxb.)Kunth. Arum tortuosum.