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Persicaria amphibia
Also called Water Smartweed, Water knotweed, Longroot smartweed, Scarlet Smartweed
Amphibious bistort is a creeping or floating perennial herb of wet places, found in ponds, streams, marshes and damp meadows across the Northern Hemisphere. It grows best with its roots in moist soil or shallow water and is often grown as a pond or bog plant.
Persicaria amphibia (syn. Polygonum amphibium) is a species of flowering plant in the knotweed family known by several common names, including longroot smartweed, water knotweed, water smartweed, and amphibious bistort. It is native to much of North America, Asia, Europe, and parts of Africa, and it grows elsewhere as an introduced species and sometimes a noxious weed.
Persicaria amphibia is native to a large area across the northern hemisphere, including Europe, Asia, North America, and parts of Africa. It has been introduced elsewhere, such as South America and other parts of Africa.
Various parts of this plant were used by several Native American groups as medicinal remedies and sometimes as food.
Pink Headed Knotweed · Chinese Knotweed · Water pepper · Curlytop knotweed · Redshank · Persicaria microcephala · Small water-pepper · Vietnamese Coriander · Pinkweed · Asiatic Tearthumb · Dotted Smartweed · Persicaria tinctoria
Text excerpted from the Wikipedia article Persicaria amphibia 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.
