The Temperate Database is in the process of being updated, with new records being added and old ones being checked and brought up to date where necessary. This record has not yet been checked and updated.
Polygala japonica is a perennial plant that can grow up to 0.20 metres tall.
It is harvested from the wild for local use as a food and medicine
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.
E. Asia - China, Japan, Korea.
Grassy slopes in lowland and hills all over Japan[
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.
Young leaves - cooked[
Root - cooked. The core is removed and the root is boiled in several changes of water[
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[
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.
Cuttings of young shoots in a frame in late spring[