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Persicaria maculosa
Also called Red shank, Lady's Thumb, Spotted Lady's Thumb, Spotted Ladysthumb, Jesusplant, Redleg, Blackheart
Redshank is a fast-growing annual weed of the buckwheat family, usually found in disturbed ground, roadsides and riverbanks rather than cultivated. It is grown mainly as a wild edible or dye plant, and it spreads quickly from seed.
Persicaria maculosa (syn. Polygonum persicaria) is an annual plant in the buckwheat family, Polygonaceae. Common names include lady's thumb, spotted lady's thumb, Jesusplant, and redshank. It is widespread across Eurasia from Iceland south to Portugal and east to Japan. It is also present as an introduced and invasive species in North America, where it was first noted in the Great Lakes region in 1843 and has now spread through most of the continent.
Persicaria maculosa contains persicarin and tannins. The young leaves may be eaten as a leaf vegetable. It is often seen as a weed and rarely cultivated. A yellow dye can be produced from this plant with alum used as a mordant.
Persicaria maculosa is native to Europe and Asia, where it can be mistaken for Polygonum minus. The latter has narrower leaves, usually less than 1 cm wide. It has been introduced to North America and is naturalised throughout the mainland continent, growing along roadsides, riverbanks, and on fallow ground. In the United States, it is very similar to Pennsylvania smartweed, but redshank has a fringe of hairs at the top of the ochrea, something which Pennsylvania smartweed lacks. The species has also been found in New Zealand and Australia.
Amphibious Bistort · Pink Headed Knotweed · Chinese Knotweed · Water pepper · Curlytop knotweed · Persicaria microcephala · Small water-pepper · Vietnamese Coriander · Pinkweed · Asiatic Tearthumb · Dotted Smartweed · Persicaria tinctoria
Text excerpted from the Wikipedia article Persicaria maculosa by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.
