Rough potato
Metaplexis japonica

Family: Asclepiadaceae

What it is like

Metaplexis japonica is a deciduous Climber growing to 8 m (26ft 3in). It is frost tender. It is in flower from July to September. The species is hermaphrodite (has both male and female organs). Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 8

Where it is found

Sunny slopes and thickets in hills and low mountains.

E. Asia - China, Japan.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 2

Young leaves - raw or cooked. Young fruits - raw or pickled. Root - cooked.

Root: includes bulbs, corms, tubers, rhizomes etc.

Medicine

Rating: 2

The seed and the leaves are haemostatic and tonic. The hairs on the seeds are styptic whilst the pounded leaves are applied to abscesses and swellings. The stems and roots are used as medicine for traumatic injury, snake bites, impotence, and infantile malnutrition due to intestinal parasites.

Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.

Haemostatic: Controls internal bleeding.

Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.

Other

Rating:

The seed hairs could possibly be used as a stuffing material for pillows etc.

Stuffing: Used in making soft toys, mattresses, pillows etc.

How it is grown

Succeeds in ordinary garden soil. This species is not very hardy in Britain, the plants succeed outdoors in south-west England but are apt to be cut to the ground by severe frosts. Cultivated as a vegetable in China.

Propagating it: Seed - we have no information for this species but suggest sowing the seed in early spring in a greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Give the plants some protection from the cold for at least their first winter outdoors.

Best place to grow: Woodland Garden Sunny Edge; Dappled Shade; Shady Edge;

Habit: Climber

Hardiness: 0-0

Growth:

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Synonyms

M. chinensis. M. stauntonii. Pergularia japonica. Urostelma chinense.