Ranunculus reptans aka Creeping Spearwort

Ranunculus reptans, or creeping spearwort, belongs to the buttercup family, Ranunculaceae. This perennial grows in northern temperate and subarctic regions. Its native range spans Europe, northern Asia, and North America. Kew places it across the Northern Hemisphere’s cool regions. The RHS confirms that it is native to Britain and Ireland. In Britain, records include lake shores in Scotland and the Lake District. Plants For A Future describes it as rare in those places.

This low plant grows fast and spreads wider than its height. Its listed height reaches about 0.7 feet (0.2 metres). Its spread reaches about 3.3 feet (1 metre). That broad, low form matters when choosing space near other plants. Plants For A Future reports that it can hinder nearby growth. It singles out legumes as plants that may suffer. The same source does not flag it as a weed. These points distinguish its effects on neighbours from its weed status.

Flowers appear from June through August. Each flower has both male and female organs. Bees, flies, and beetles carry pollen between flowers. In cultivation, it accepts full sun or partial shade. It needs soil that stays moist or wet. A damp, fairly heavy loam is its preferred soil. It can also grow in sandy soil or clay. It accepts mildly acid, neutral, and mildly alkaline conditions. Plants For A Future reports that frost does not harm it.

Pond margins and bog gardens are listed planting sites. These settings match its need for steady soil moisture. Seed and division offer two ways to raise more plants. Sow seed in a cold frame during spring. Move seedlings into separate pots once large enough to handle. Plant them outdoors in summer. Divide established plants in spring. Plants For A Future describes division as very easy. Large divisions can go straight into their final growing sites.

All parts are poisonous, according to Plants For A Future. Its sharp sap can also cause skin blisters. The source records cooked roots as a traditional food. It describes baking the roots before dipping them in oil. It also states that heat or drying destroys the toxins. This reported use does not make the fresh plant safe. Its food-use rating is low, at one out of five. The source lists no known medicinal or other uses.