Arisaema utile
Hook.f. ex Schott.
wikimedia· cc-by
Alvesgaspar (via Wikimedia Commons)
gbif· cc0
John Kenrick Gibson
Description
Arisaema utile is a PERENNIAL growing to 0.5 m (1ft 8in) by 0.3 m (1ft). See above for USDA hardiness. It is hardy to UK zone 5. It is in flower from May to June. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required). 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.
Edible Uses
Leaves and flowering spathes - cooked as a potherb.
Known Hazards
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.
Distribution
E. Asia - Himalayas - Pakistan to Nepal and Bhutan.
Where It Grows
Coming Soon
Cultivation
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. Tubers should be planted about 10cm deep. Only plant out full sized tubers and mulch them with organic matter in the winter. Plants need protection from slugs. Closely related to A. griffithii. 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. 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.
