Ranunculus japonicus

Ranunculus japonicus belongs to the buttercup family, Ranunculaceae. It is a perennial: it lives for more than two years. Plants For A Future calls it Mao Gen. Kew gives its native range as the Russian Far East to northern Korea. This range takes in northern Honshu in Japan as well. Kew links it with subalpine or subarctic climates. Plants For A Future gives a wider native range. It lists Shaanxi in China and grassy sites across Japan. The sources thus differ on the bounds of its native range.

Plants For A Future describes a small plant that grows low. It gives a height of about 0.3 feet [0.1 metres]. It lists a spread of about 1 foot [0.3 metres]. The supplied account gives no leaf shape or stem details for this species. Nor does it state its flower colour or describe its fruit. It blooms from May through July. Each flower has both male and female organs. Insects move pollen between the flowers.

Reports place it in damp grassland, in both lowlands and mountains. Plants For A Future lists sun and light shade as suitable. It lists sandy, loamy, and clay soils as well. The stated soil range runs from mildly acid to mildly alkaline. The species summary says moist soil suits it. But the source bases its growing notes on the needs of the genus as a whole. These notes carry less weight than direct trials of this plant. The source does not confirm that it can withstand British winters. Its native range forms the basis for suggested outdoor survival there.

Plants For A Future lists garden beds as a place to grow it. It gives no full account of its value in garden design. One listed way to grow new plants is to sow seeds in spring. The source says to use a cold frame at this stage. Once young plants grow large enough to handle, move them to their own pots. It then suggests planting them outside in summer. Dividing plants in spring is another way to grow more. The supplied evidence gives no pest or disease details for this species.

Reports list food uses for the leaves, but also warn of poison. Plants For A Future lists cooked leaves as edible. It says toxicity is low. It also says heat or drying can destroy the toxins. This does not show a safe serving size or way to prepare them. The source records uses as medicine for congestion, worms, and malaria. It reports compounds that act against tumours. This is not proof of a safe treatment. Its ratings for food and medicine are both low.