Potentilla simplex aka Common Cinquefoil

Potentilla simplex is a low perennial in the rose family. Its common names include old field cinquefoil and common cinquefoil. It comes from eastern Canada and the central and eastern United States. Its range includes Ontario, Québec, and the Atlantic provinces. In the United States, it reaches from New England south to Texas and Louisiana. It grows in temperate regions and is not native to Britain or Ireland. Wild plants occur in open, dry woods and on prairie slopes. They also grow along roads, in old fields, and on disturbed ground.

Plants reach about 0.3 feet [0.1 metres] tall. They spread to about 1.6 feet [0.5 metres] across. This low form suits the edge of a woodland garden. A sunny edge or a site with light shade offers suitable conditions. Flowers appear from June to August. Each flower has both male and female organs. Insects pollinate the flowers, and the plant is self-fertile. Rich soil can lead to more leaf growth but fewer flowers.

This species is easy to grow in soil that drains well. Loam suits it, though it also accepts sand and clay. It prefers full sun but can tolerate some shade. It favours alkaline soil, yet accepts neutral and slightly acid ground. In cultivation, it prefers moist soil despite growing in some dry wild habitats. PFAF lists USDA zones 3–7 and cold tolerance near −13°F [−25°C]. The plant has some weed potential, which merits thought when choosing its place.

Gardeners can raise plants from seed or divide them in spring. Sow seed in a cold frame in early spring or autumn. Move seedlings into separate pots once they are large enough. Keep them in a greenhouse through their first winter. Plant them outside in late spring or early summer, after frost risk passes. Large divisions can go straight into their final sites. Grow smaller divisions under light shade in a cold frame until well rooted.

PFAF lists no known edible uses and no known hazards. That record does not establish safety for people or pets. It reports past medicinal use as a mild astringent and antiseptic. Traditional uses include a mouth rinse for gum problems. A root infusion has also been used for dysentery. These records describe past use, not proven treatment.