Tian Nan Xing
Arisaema amurense
Family: Araceae
What it is like
Arisaema amurense is a PERENNIAL growing to 0.5 m (1ft 8in) by 0.5 m (1ft 8in). See above for USDA hardiness. It is hardy to UK zone 5. 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.
Height (m): 0.5
Where it is found
Virgin forests, mountains and river banks. Deciduous forest, mixed forest, under woods and by streams at elevations of 50 - 200 metres in China.
E. Asia - N. China, Japan, Korea.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Well-soaked roots can be boiled, peeled and eaten. The tuber is 6 - 7cm in diameter. Some caution is advised, see the notes above on toxicity. Young leaves - cooked. Some caution is advised, see the notes above on toxicity.
Root: includes bulbs, corms, tubers, rhizomes etc.
Medicine
Rating: 3
Tian Nan Xing has been used in Chinese herbal medicine for thousands of years and is valued especially for its beneficial affect upon the chest. When prescribed internally it is always used dried and in conjunction with fresh ginger root. The root is an acrid irritant herb that is anodyne, antibacterial, antifungal, antiphlogistic, antirheumatic, anticancer, antispasmodic, antitumor, expectorant, sedative and stomachic. The dried root is used internally in the treatment of coughs with profuse phlegm, tumours, cervical cancer, epilepsy, tetanus and complaints involving muscular spasms. The fresh root is applied externally as a poultice to ulcers and other skin complaints. The root is harvested when the plant is dormant in the autumn or winter and is dried for later use.
Anodyne: Relieves pain, it is milder than an analgesic.
Antispasmodic: Relaxes muscular spasms and cramps, calming nervous irritation.
Cancer: Used in the treatment of cancer.
Epilepsy: Used in the treatment of Epilepsy - a disorder in which nerve cell activity in the brain is disturbed, causing seizures.
Expectorant: Clears phlegm from the chest by inducing coughing.
Vermifuge: Expels and kills internal parasites.
Other
Rating:
How it is grown
Prefers a cool peaty soil in the bog, 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 exposed. This species is well suited to the front of a peat border. Tubers should be planted about 15cm deep. Only plant out full sized tubers and mulch them with organic matter in the winter. 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.
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: 4-8
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.