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Polygonum arenastrum
Also called Common knotweed, Doorweed, Matweed, Ovalleaf knotweed, Prostrate knotweed, Equal Leaved Knotgrass, Small Leaved Wireweed
Oval-leaf knotweed (Polygonum arenastrum) is a low, mat-forming summer annual weed in the buckwheat family, native to Eurasia and now widespread in North America. It thrives in compacted soil and drought, so it is hard to keep out of lawns and gardens.
Polygonum arenastrum, commonly known as equal-leaved knotgrass, is a summer annual flowering plant in the knotweed family Polygonaceae. Other common names include common knotweed, prostrate knotweed, mat grass, oval-leaf knotweed, stone grass, wiregrass, and door weed, as well as many others. It is native to Eurasia and can be found on other continents as an introduced species and a common noxious weed. Knotweed was first seen in North America in 1809 and is now seen across much of the United States and Canada.
European knotweed · Prostrate knotweed · Indian Knotgrass · Douglas' knotweed · Erect knotweed · Knotweed
Text excerpted from the Wikipedia article Polygonum arenastrum 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.
