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Polygonum ramosissimum
Also called Tall Knotweed, Yellow Knotweed, Yellow Flower Knotweed, Yellow Flowered Knotweed, Smartweed
Bushy knotweed is a North American wild annual herb in the buckwheat family, typically found as a weedy plant of disturbed ground rather than a cultivated garden plant. It is grown only rarely, and mainly by those interested in native plants.
Polygonum ramosissimum is a North American species of herbaceous annual plants in the buckwheat family, widespread across much of Canada and the United States, where it is commonly called bushy knotweed. It is susceptible to downy mildew caused by the oomycete species Peronospora americana.
Leathery knotweed · Knotweed · Polygonum albanicum · Polygonum amgense · European knotweed · Oval-leaf knotweed · Austin's Knotweed · Prostrate knotweed · Narrowleaf knotweed · Bidwell's knotweed · Bolander's knotweed · Northern Knotgrass
Text excerpted from the Wikipedia article Polygonum ramosissimum 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.
