Potentilla is a large and taxonomically complex genus of flowering plants in the rose family (Rosaceae), subfamily Rosoideae. The genus is universally known by the common name cinquefoil, a word derived from Old French cinc and Latin quinque — both meaning "five" — combined with feuille ("leaf"), in reference to the palmately five-parted leaves characteristic of many species. The scientific name Potentilla itself is more obscure in origin and is generally interpreted as a fusion of ancient plant names, with possible influence from the Latin poterium (used for burnets). Carl Linnaeus formally described the genus in 1753, designating Potentilla reptans, the European or creeping cinquefoil, as the type species.
Plants in the genus are mostly herbaceous perennials, with a smaller number of small shrubs and a few annuals. The leaves are compound, stipulate, and either palmate or pinnate, with anywhere from three to fifteen or more leaflets depending on the species. Flowers are saucer-shaped to hemispheric, typically arranged with five sepals, five petals, and numerous stamens. Petal colour is most commonly bright yellow, but white, pink, scarlet and dark blood-red flowers occur, particularly in horticultural selections. The fruit is a cluster of dry, inedible achenes — a feature that distinguishes Potentilla from the superficially similar Fragaria (strawberries), with which the genus shares an overall floral plan.
The modern circumscription of the genus is the result of repeated taxonomic revisions. Plants of the World Online currently accepts more than five hundred species, after the recent inclusion of Horkelia, Ivesia and Duchesnea within Potentilla. At the same time, several groups long treated as cinquefoils have been segregated out: the shrubby species into Dasiphora, the tall herbaceous "drymocalli" into Drymocallis, the marsh cinquefoil into Comarum, the three-toothed cinquefoil into Sibbaldiopsis, and the silverweeds into Argentina. Many species are polyploid, apomictic, or both, which contributes to the difficulty of species delimitation across the genus.
Cinquefoils have a broadly holarctic distribution, occurring across the northern continents of Europe, Asia and North America, with outliers reaching the montane biomes of the New Guinea Highlands. They are well represented in cool and cold regions and form a conspicuous component of moorlands, heathlands, alpine meadows, grasslands, wetlands and rocky habitats. Switzerland alone hosts more than forty species, spanning alpine zones (P. aurea, P. crantzii), wet ground (P. palustris), open rocks (P. nitida, P. rupestris) and agricultural margins (P. anserina, P. recta).
Etymology
The common name cinquefoil comes from Old French cinc and Latin quinque, both meaning "five", joined to feuille or foil ("leaf") — a direct reference to the five leaflets typical of the palmate leaves found in many species of the genus. The scientific name Potentilla is less transparent. It has been interpreted as a fusion of ancient plant names, with proposed influences from the Latin poterium (used in classical times for burnets, Sanguisorba / Poterium) and possibly Dacian plant names borrowed into Latin botanical literature.
Distribution
Potentilla is one of the most characteristic genera of the holarctic flora, occurring across the cool and temperate zones of the Northern Hemisphere — Europe, North Africa, temperate and montane Asia and North America. A small number of species reach the montane biomes of the New Guinea Highlands south of the equator. Regional diversity is high in temperate floras: more than forty species occur in Switzerland alone, and floras of the American Southwest list endemic taxa such as P. arizonica and P. anachoretica alongside the widespread P. fruticosa and P. anserina. Globally, SEINet cites an older estimate of roughly two hundred species, while Plants of the World Online now accepts well over five hundred following the inclusion of Horkelia, Ivesia and Duchesnea.
Ecology
Cinquefoils are a prominent component of many cool-temperate, alpine and boreal ecosystems. In the British Isles they are a recognisable element of moorland and heathland communities alongside heather, birch and tussock grasses. In the Alps and other mountain ranges, alpine species such as P. aurea, P. crantzii and P. nitida colonise short turf and rocky ground at high elevations, while P. palustris is a wetland specialist. Lowland representatives like P. anserina (silverweed) and P. recta (sulphur cinquefoil) are typical of grasslands, riverbanks, roadsides and disturbed agricultural ground. The genus's ecological breadth — from desert margins in the American Southwest to alpine fellfield — reflects both its long evolutionary history and the high incidence of polyploidy and apomixis among its species.
Cultivation
Several Potentilla species are well established in temperate gardens. Missouri Botanical Garden's Plant Finder lists around twenty taxa in cultivation, dominated by the shrubby cinquefoil (P. fruticosa, now often placed in Dasiphora) with numerous named cultivars such as 'Abbotswood', 'Coronation Triumph', 'Dakota Sunspot', 'Hallman Dwarf' and 'Cheesehead', alongside herbaceous border species including P. atrosanguinea, P. nepalensis, P. recta, P. argentea, P. neumanniana, P. rupestris and P. thurberi. Horticultural development of the genus dates at least to Victor Lemoine's introduction of the double-flowered P. 'Gloire de Nancy' in 1854.
General requirements are undemanding: most species are easily grown in well-drained loam in full sun, tolerate light shade, thrive in slightly alkaline soils, and accept moist as well as average conditions. P. anserina is noted to spread vigorously by running stems and roots and can become invasive in cultivation, so siting and confinement matter.
Conservation
At the genus level, Potentilla is not listed in the IUCN/ISSG Global Invasive Species Database (the entry states that the genus "is not present yet in our archive"). No global Red List status applies to the genus as a whole; conservation concern in Potentilla is species-specific, with some alpine and wetland taxa locally rare and others (such as P. recta and P. indica) regionally considered weedy or invasive in floras outside their native range.
Cultural uses
Several cinquefoils have a long history of human use. The roots of silverweed (P. anserina) were traditionally eaten raw, cooked, or dried and ground into a flour-like meal used in soups or mixed with cereals; their taste is described as crisp and nutty with a starchy character. Young shoots are edible raw, and the leaves are brewed as tea.
Medicinally, Potentilla species are valued chiefly for their astringency, owing to a high tannin content. P. anserina is recorded as antispasmodic, mildly astringent, diuretic, haemostatic and tonic; strong infusions are used for diarrhoea and to staunch hemorrhage, and external preparations treat ulcers and provide local pain relief. The German Commission E approves silverweed for diarrhoea, mouth inflammation and premenstrual symptoms. Common tormentil (P. erecta) is even more strongly astringent and has been used as a herbal remedy for inflammation and gastrointestinal disorders. In traditional Chinese medicine, P. discolor and P. multifida are used in the treatment of diabetes. Folk uses recorded for silverweed include placing a sprig inside a shoe to prevent blisters and applying leaf infusions as a skin-cleansing wash.
History
Linnaeus formally established Potentilla in Species Plantarum (1753), with P. reptans as the type species. The genus has been continuously rich ground for botanists ever since, owing to its size, the prevalence of polyploidy and apomixis, and the difficulty of distinguishing closely related forms. Horticulturally, the modern era of cinquefoils as garden plants began with the French nurseryman Victor Lemoine, whose double-flowered selection P. 'Gloire de Nancy' was introduced in 1854 and inaugurated a long line of cultivars.
Taxonomy notes
Potentilla L. is placed in family Rosaceae, subfamily Rosoideae, order Rosales. Plants of the World Online currently accepts more than five hundred species, after the inclusion of the formerly recognised genera Horkelia, Ivesia and Duchesnea. Conversely, several historical Potentilla groups have been transferred out as molecular work refined the phylogeny: the shrubby species to Dasiphora, the tall herbaceous "drymocalli" to Drymocallis, the marsh cinquefoil to Comarum, the three-toothed cinquefoil to Sibbaldiopsis, and the silverweeds (including the widely used P. anserina) to Argentina. Older floras and some regional treatments (such as SEINet) still cite circumscriptions of roughly two hundred species, reflecting the pre-merger view. A high incidence of polyploidy and apomixis across the genus contributes to ongoing difficulty in species delimitation.
