Oenothera biennisL.

common evening-primrose

WFO wfo-0000389564 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Oenothera biennis, photographed by Dilrukshan Priyantha Wijesinghe
fig. a Dilrukshan Priyantha Wijesinghe, CC BY 4.0 / 2022-06-06 / obs. 204154396
Oenothera biennis, photographed by Violet T.
fig. b Violet T., CC BY 4.0 / obs. 199826670
Oenothera biennis, photographed by Kim
fig. c Kim, CC BY 4.0 / obs. 172926496
Oenothera biennis, photographed by Jamie VanBuskirk
fig. d Jamie VanBuskirk, CC BY 4.0 / obs. 180361259
Oenothera biennis, photographed by Cecil Smith
fig. e Cecil Smith, CC BY 4.0 / obs. 183987849
Oenothera biennis, photographed by Navin Sasikumar
fig. f Navin Sasikumar, CC BY 4.0 / obs. 194481819
Oenothera biennis, photographed by Eric Schmidt
fig. g Eric Schmidt, CC BY 4.0 / obs. 172735264
Oenothera biennis, photographed by Violet T.
fig. h Violet T., CC BY 4.0 / obs. 180270999

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Flowering n = 3,971 observations

Peak flowering in Aug, from 3,971 community-annotated observations worldwide. This is a global aggregate, not a forecast for your garden: the same species flowers on different dates in different hemispheres, and citizen-science records cluster near cities, at weekends, and in spring. Where a species has fewer than 30 annotated records we do not draw this chart at all.

Also published as 130 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Brunyera biennis (L.) Bubani
  • Oenothera beckeri Renner
  • Oenothera biennis f. biennis
  • Oenothera biennis f. leptomeres (Bartlett) P.D.Sell
  • Oenothera biennis f. muricata (L.) H.Lév. ex Thell.
  • Oenothera biennis f. nanella de Vries
  • Oenothera biennis subf. latifolia (Asch.) Thell.
  • Oenothera biennis subsp. biennis Thell.
  • Oenothera biennis subsp. caeciarum Munz
  • Oenothera biennis subsp. centralis Munz
  • Oenothera biennis subsp. chicaginensis (de Vries ex Renner & Cleland) Á.Löve & D.Löve
  • Oenothera biennis subsp. grandiflora Stomps
  • Oenothera biennis subsp. rubricaulis (Kleb.) Stomps
  • Oenothera biennis subsp. suaveolens (Pers.) Rouy & E.G.Camus
  • Oenothera biennis var. alba Alef.
  • Oenothera biennis var. angustifolia Renner
  • Oenothera biennis var. biennis
  • Oenothera biennis var. cantabrigiana B.M.Davis
  • Oenothera biennis var. grandiflora (L'Hér.) Lindl.
  • Oenothera biennis var. leptomeres Bartlett
  • Oenothera biennis var. lutea Alef.
  • Oenothera biennis var. muricata (L.) Torr. & A.Gray
  • Oenothera biennis var. parviflora Abrom.
  • Oenothera biennis var. pycnocarpa Wiegand

and 106 more.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.

We publish what we can source and we say so when we cannot. This page has no care advice, no toxicity claim and no native range, because we do not yet have those from a source we can cite.