Hypericum kamtschaticum

Hypericum kamtschaticum is known as Kamchatka St John's wort. It belongs to the Hypericaceae family. Its native range runs from Russia's Far East to northern Japan. Records include Kamchatka, Primorye, Sakhalin, and the Kuril Islands. In Japan, it grows on Hokkaido and Honshu. Plants For A Future places it in alpine areas of northern and central Japan. Kew lists it as a plant of temperate regions. It is not native to Britain or Ireland.

This small plant reaches about 1 foot [0.3 metres] tall. Plants For A Future describes it as a perennial. Kew allows for either a perennial or a subshrub form. The supplied sources give no mature width. They also lack species-level details on leaves, stems, and fruit. Each flower has both male and female organs. Insects pollinate the flowers, and the plant is self-fertile. The evidence does not establish its flower colour or bloom season.

Plants For A Future lists moist soil with good drainage. It accepts sandy, loamy, and clay soils. Its stated pH range runs from mildly acid to mildly alkaline. The species entry allows both light shade and full sun. The site's further growing notes draw on the genus as a whole. These suggest that sun gives better flowering, but lack species-specific confirmation. The source also says its knowledge of this species is limited. It expects British hardiness from the native range, rather than confirmed trials. No precise hardiness zone is supplied.

The source lists cultivated beds as a garden setting. It gives spring sowing and spring division as propagation methods. Cover seed only lightly when sowing in a greenhouse. Germination can take one to three months at 50°F [10°C]. Grow seedlings in separate pots through their first winter under cover. Set them outside after the last expected frost. Large divisions can go straight into their final sites. Keep smaller divisions in pots until their roots grow well.

Plants For A Future lists leaves and shoots as edible parts. It records cooked young growth and shoot tips as food. Its food-use rating is low, at one out of five. It reports no known medicinal or other uses. It lists no known hazards, but this does not prove safety. The supplied evidence gives no species-specific pest or disease details.