Swertia bimaculata

Swertia bimaculata is in the gentian family, also called Gentianaceae. It is an annual or biennial herb. Kew gives its native range as eastern Nepal to Japan and northern Indo-China. Plants For A Future lists a wider range in Asia. It includes China, Taiwan, Bhutan and India. It also includes Myanmar, Vietnam, Malaysia and Indonesia. The RHS lists it as non-native to Britain and Ireland. An older name for it is Ophelia bimaculata.

The plant grows to about 2 feet [0.6 metres] tall. The sources give no spread or full account of its leaves. They give no details of its stems or fruit. Plants For A Future says it flowers in September. Each flower has both male and female organs. The evidence does not say what insects or other agents pollinate it. Its short life sets it apart from border plants that live for years.

In Japan, it grows in wet grassland. It occurs from the lowlands up into the mountains. Records from China place it by streams, in swamps and in meadows. It also grows in scrub and forest. These records span heights of 656–9,843 feet [200–3,000 metres]. Kew calls its climate temperate. These records show where it grows in the wild. They do not show how it will grow in every garden.

Plants For A Future suggests moist soil that drains well. It advises a sunny site but lists light shade as suitable too. It lists sand, loam and clay as soils it tolerates. It accepts mildly acid, neutral and mildly alkaline soil. The source lists USDA zones 6–9 and mentions beds used for growing plants. Its growing advice is not firm, as it lacks full records of growing this plant. It advises sowing seeds in a cold frame in spring. Keep the temperature at 10°C or below. Move seedlings to their own pots when large enough to handle. Plant them out in summer.

Plants For A Future lists the cooked root as edible. It gives the plant a low rating for food use. It lists no known uses in medicine or other practical uses. The same source reports no known hazards. This does not prove it is safe for people or pets. It does not flag the species as weedy. The evidence names no pests or diseases. It gives no flower colour or details of its effect in a landscape.