Common Name:

General Information

Viola japonica is a stemless, herbaceous, perennial plant forming a rosette of leaves and growing around 20cm tall.
The plant is harvested from the wild for local use as a food and a medicine. It is grown as an ornamental in gardens.

Known Hazards

All members of this genus have more or less edible leaves and flower buds, though those species with yellow flowers can cause diarrhoea if eaten in large quantities[, , ].The flowers of this species are usually light purplish or whitish violet[].

Botanical References

, ,

Range

E. Asia - Japan, Korea, south Taiwan

Habitat

Sunny or semi-shaded places in lowland areas; at elevations below 1,100 metres[, ]. Hillsides and damp places in China[].

Properties

Edibility Rating
Medicinal Rating
Habit	Perennial
Height	0.20 m
Pollinators	Insects
Cultivation Status	Ornamental, Wild

Cultivation Details

Prefers a cool moist well-drained humus-rich soil in partial or dappled shade and protection from scorching winds. Tolerates sandstone and limestone soils but becomes chlorotic if the pH is too high. Prefers a pH between 6 and 6.5[].
All members of this genus have more or less edible leaves and flower buds, though those species with yellow flowers can cause diarrhoea if eaten in large quantities[, , ]. The flowers of this species are light purplish or whitish violet[].

Edible Uses

Young leaves and flower buds - raw or cooked[]. When added to soup they thicken it in much the same way as okra[, ]. The flowers are light purplish or whitish violet[].

Root - cooked. Mucilaginous[]. Rich in starch, it is eaten in soups[].

A tea can be made from the leaves[].

Medicinal

The whole plant is anodyne, anti-inflammatory, antiphlogistic and depurative[, ]. A decoction is used in the treatment of abscesses, boils, acute conjunctivitis, hepatitis, acute jaundice, laryngitis and ulcers[, , ].

Other Uses

None known

Propagation

Seed - best sown in the autumn in a cold frame. Sow stored seed in early spring in a cold frame. Prick out the seedlings into individual pots when they are large enough to handle and plant them out in the summer.
Division in the autumn or just after flowering. Larger divisions can be planted out direct into their permanent positions, though we have found that it is best to pot up smaller divisions and grow them on in light shade in a greenhouse or cold frame until they are growing away well. Plant them out in the summer or the following spring.