Iris pseudacorusL.

Yellow Iris

WFO wfo-0000783754 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Iris pseudacorus, photographed by snaily_naily
fig. a snaily_naily, CC BY 4.0 / 2022-06-13 / obs. 205762525
Iris pseudacorus, photographed by harrier
fig. b harrier, CC BY 4.0 / obs. 205952406
Iris pseudacorus, photographed by Erin Springinotic
fig. c Erin Springinotic, CC0 1.0 / obs. 205573099
Iris pseudacorus, photographed by DeeF
fig. d DeeF, CC BY 4.0 / obs. 205630887
Iris pseudacorus, photographed by Aleksei Baushev
fig. e Aleksei Baushev, CC BY 4.0 / obs. 205250851
Iris pseudacorus, photographed by Aleksei Baushev
fig. f Aleksei Baushev, CC BY 4.0 / obs. 205236043
Iris pseudacorus, photographed by Rachel Webster
fig. g Rachel Webster, CC0 1.0 / obs. 205227938
Iris pseudacorus, photographed by Нурхайдарова Татьяна
fig. h Нурхайдарова Татьяна, CC BY 4.0 / obs. 205186070

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 = 6,607 observations

Peak flowering in May, from 6,607 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 41 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.

  • Acorus adulterinus Ludw.
  • Acorus adulterinus Garsault
  • Iris acoriformis Boreau
  • Iris acoroides Spach
  • Iris bastardii Boreau
  • Iris curtopetala F.Delaroche
  • Iris curtopetala Redouté
  • Iris flava Tornab.
  • Iris lutea Ludw.
  • Iris lutea Lam.
  • Iris pallidior Hill
  • Iris paludosa Pers.
  • Iris palustris Gaterau
  • Iris palustris Moench
  • Iris palustris var. pallida Gray
  • Iris pseudacorus f. albescens Neuman
  • Iris pseudacorus f. longiacuminata Prodan
  • Iris pseudacorus f. nyaradyana Prodan
  • Iris pseudacorus f. submersa Glück
  • Iris pseudacorus subsp. acoriformis (Boreau) K.Richt.
  • Iris pseudacorus subsp. bastardii (Boreau) K.Richt.
  • Iris pseudacorus subvar. aurantiaca Druce
  • Iris pseudacorus var. acoriformis (Boreau) Baker
  • Iris pseudacorus var. acoriformis (Boreau) Nyman

and 17 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.