Onagraceae
Square-stemmed willowherb
Epilobium tetragonum
- Family
- Onagraceae
- Genus
- Epilobium
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Common names
By language (21)
- Belarusian
- Скрыпень чатырохгранны
- Czech
- Vrbovka čtyřhranná
- Dutch
- Kantige basterdwederik
- English
- Square-stemmed willowherb, Square stalked willow herb
- Esperanto
- Anguleca epilobio
- Estonian
- Laskuvalehine pajulill
- Finnish
- Särmähorsma
- French
- Epilobe à tige carrée, Épilobe à quatre angles, Épilobe à tiges carrées, Épilobe à tiges quadrangulaires
- German
- Vierkantiges Weidenröschen, Vierkantiges Weidenrüschen
- hsb
- Hranitkata wjerbinka
- Hungarian
- Négyélű füzike
- kw
- Helygles korsen bedrek
- Lithuanian
- Keturbriaunė ožkarožė
- Norwegian Bokmål
- Kantmjølke
- Persian
- بید علفی چهارگوش
- Polish
- Wierzbownica czworoboczna, Wierzbownica czteroboczna
- Romanian
- Pufuliță
- Russian
- Кипрей четырёхгранный, Кипрей сродный, Кипрей четырёхсторонний, Кипрей четырёхугольный
- Slovenian
- Robatostebelni vrbovec
- Swedish
- Kantdunört
- Welsh
- Helyglys pedronglog
Synonyms
- Chamaenerion tetragonum (L.) Scop.
- Epilobium adnatum var. rodriguezii Sennen
- Epilobium decurrens hort.
- Epilobium dubium Curt.
- Epilobium glabellum var. tetragonum (L.) Maiden & Betche
- Epilobium tetragonum subsp. adnatum (Griseb.) Cabanès
Flowers
- In flower
- June to August (from 97 flowering iNaturalist observations worldwide)
Photos
FlowerPhoto: Andrey Sdobnikov, CC BY 4.0, from iNaturalist 
FlowerPhoto: Markus Krieger, CC BY 4.0, from iNaturalist 
FlowerPhoto: Георгий Виноградов (Georgy Vinogradov), CC BY 4.0, from iNaturalist 
FlowerPhoto: Duarte Frade, CC BY 4.0, from iNaturalist 
Photo: Rasbak, CC BY-SA 3.0, from Wikimedia Commons 
Photo: Ljaž, CC BY 4.0, from iNaturalist 
Photo: AnRo0002, CC0, from Wikimedia Commons 
Photo: Jeremy Gilmore, CC BY 4.0, from iNaturalist 
Photo: AnRo0002, CC0, from Wikimedia Commons 
Photo: Andrew Skotnicki, CC BY 4.0, from iNaturalist 
Photo: AnRo0002, CC0, from Wikimedia Commons 
Photo: Fabien Piednoir, CC BY-SA 4.0, from iNaturalist
More in Epilobium
- FireweedEpilobium angustifoliumOnagraceae
- Great willowherbEpilobium hirsutumOnagraceae
- Broad-leaved willowherbEpilobium montanumOnagraceae
- Marsh willowherbEpilobium palustreOnagraceae
- Smallflower hairy willowherbEpilobium parviflorumOnagraceae
- Epilobium collinumOnagraceae
- Pimpernel willowherbEpilobium anagallidifoliumOnagraceae
- Fringed willowherbEpilobium ciliatumOnagraceae
- Dwarf fireweedEpilobium latifoliumOnagraceae
- Chickweed willowherbEpilobium alsinifoliumOnagraceae
- Spear leaved willow herbEpilobium lanceolatumOnagraceae
- Dwarf willowherbEpilobium obscurumOnagraceae
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). About our plant data.