helloplants.org

Polygala japonica

Family: Polygalaceae


What it is like

Polygala japonica is a PERENNIAL growing to 0.3 m (1ft). The species is hermaphrodite (has both male and female organs). Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. 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): 0.3


Where it is found

Grassy slopes in lowland and hills all over Japan.

E. Asia - China, Japan, Korea.

Conservation Status:

Countries/locations it is found in


How it is used

Food

Rating: 1

Young leaves - cooked. Root - cooked. The core is removed and the root is boiled in several changes of water.

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

Medicine

Rating: 2

The dried root is used in the treatment of tuberculosis. It is an expectorant tonic. The plant is antiphlogistic, antitussive, carminative, depurative, expectorant and tonic. A decoction is used in the treatment of upper respiratory tract infections, inadequate measles eruption, palpitation and insomnia, traumatic injuries and snakebites.

Antiphlogistic: Reduces inflammation.

Antitussive: Prevents or relieves coughing.

Carminative: Reduces flatulence and expels gas from the intestines.

Depurative: Eliminates toxins and purifies the system, especially the blood.

Expectorant: Clears phlegm from the chest by inducing coughing.

TB: Plants used in the treatment of tuberculosis

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

Other

Rating:


How it is grown

We have very little information on this species and do not know if it will be hardy in Britain, though judging by its native range it should succeed outdoors in most parts of this country. The following notes are based on the general needs of the genus. Prefers a moderately fertile moisture-retentive well-drained soil, succeeding in full sun if the soil remains moist throughout the growing season, otherwise it is best in semi-shade. Dislikes shade according to another report.

Propagating it: Seed - sow spring or autumn in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Division. Cuttings of young shoots in a frame in late spring.

Best place to grow: Cultivated Beds;

Habit: Perennial

Hardiness:

Growth:

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

Shade: Semi-shade, no shade

Moisture: Moist


Things to keep in mind

Although no specific mention has been seen for this species, at least one member of this genus is said to be poisonous in large quantities.


Its other names

Local names

Synonyms