Polygonaceae

Common knotweed

Polygonum plebeium R.Br.

Family: Polygonaceae
Genus: Polygonum

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Common knotweed (Polygonum plebeium) — FlowerPhoto: grampianshiker, CC BY 4.0, from iNaturalist

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Common names

By language (5)

Arabic: بطباط رصاصي
Bangla: চিমটি শাক | খুদি বিষকাঁটালি | মেছুয়া শাক | রাণীফুল
Chinese: 习见蓼, 假扁蓄, 习见寥, 习见萹蓄, 小萹蓄, 桃叶蓼, 節花路蓼, 腋花蓼
English: Common knotweed
Odia: ମୁଠି ଶାଗ

Synonyms

Avicularia indica Didrichs.
Polygonum aviculare var. minutiflorum Franch.
Polygonum changii Kitag.
Polygonum dryandri Spreng.
Polygonum herniarioides Delile
Polygonum humifusum var. mandshuricum Skvortsov
Polygonum parviflorum Y.L.Chang & S.X.Li
Polygonum plebeium subsp. changii (Kitag.) Vorosch.
Polygonum roxburghii Meisn.

Flowers

In flower: August, December to May (from 77 flowering iNaturalist observations worldwide)

Characteristics

Growth habit: Forb/herb
Lifespan: Annual, Perennial
In the US and Canada: Lower 48 states: introduced

Photos

FlowerPhoto: grampianshiker, CC BY 4.0, from iNaturalist
FlowerPhoto: Petra Holland, CC BY 4.0, from iNaturalist
FlowerPhoto: Andrew Hankey, CC BY-SA 4.0, from iNaturalist
FlowerPhoto: S.MORE, CC0, from iNaturalist
FlowerPhoto: Dinesh Valke, CC BY-SA 4.0, from iNaturalist
Photo: J.M.Garg, CC BY 3.0, from Wikimedia Commons
Photo: Cheng-Tao Lin, CC BY 4.0, from iNaturalist
Photo: Dinesh Valke from Thane, India, CC BY-SA 2.0, from Wikimedia Commons
Photo: Dinesh Valke from Thane, India, CC BY-SA 2.0, from Wikimedia Commons
Photo: dune_ninja, CC0, from iNaturalist
Photo: Dinesh Valke from Thane, India, CC BY-SA 2.0, from Wikimedia Commons
Photo: Siva Naturewild, CC BY 4.0, from iNaturalist

More in Polygonum

Sources: classification, synonyms from World Flora Online Plant List (2026-06, CC0 1.0); common names, popularity from Wikidata (2026-10-26, CC0 1.0); common names, US characteristics from USDA PLANTS Database (2025-05-29, CC0 1.0). About our plant data.