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Polygonum douglasii
Also called Douglas's Knotweed
Douglas' knotweed is a small annual wild herb of the buckwheat family, native to much of northern and western North America, found in disturbed ground. It is a variable species complex rather than one plant with a single fixed form, and it is grown only as a wild or native-garden plant, not a common cultivated ornamental.
Polygonum douglasii is a species of flowering plant in the knotweed family known by the common name Douglas's knotweed. It is native to much of northern and western North America, where it can be found in many types of habitat, including disturbed areas. It has been found in Canada from British Columbia north to Yukon and east as far as Québec, and in the United States as far south as California, New Mexico, Iowa, and New York.
Polygonum douglasii is known as a species complex, as there are many subspecies that may be better treated as species in their own right.
European knotweed · Oval-leaf knotweed · Prostrate knotweed · Indian Knotgrass · Erect knotweed · Knotweed
Text excerpted from the Wikipedia article Polygonum douglasii 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.
