Parthenium hysterophorusL.

Santa Maria feverfew

WFO wfo-0000065156 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Parthenium hysterophorus, photographed by Joseph Aubert
fig. a Joseph Aubert, CC BY 4.0 / 2022-05-30 / obs. 202080618
Parthenium hysterophorus, photographed by rockybajada
fig. b rockybajada, CC0 1.0 / obs. 199869211
Parthenium hysterophorus, photographed by Joseph Aubert
fig. c Joseph Aubert, CC BY 4.0 / obs. 200912956
Parthenium hysterophorus, photographed by Don Loarie
fig. d Don Loarie, CC BY 4.0 / obs. 203745054
Parthenium hysterophorus, photographed by saltyhiker
fig. e saltyhiker, CC BY 4.0 / obs. 204766138
Parthenium hysterophorus, photographed by Kevin Faccenda
fig. f Kevin Faccenda, CC BY 4.0 / obs. 204064632
Parthenium hysterophorus, photographed by Ricard Busquets Reverte
fig. g Ricard Busquets Reverte, CC BY 4.0 / obs. 198721533
Parthenium hysterophorus, photographed by Ricard Busquets Reverte
fig. h Ricard Busquets Reverte, CC BY 4.0 / obs. 202510865

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 = 1,921 observations

Peak flowering in Apr, from 1,921 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 9 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.

  • Argyrochaeta bipinnatifida Cav.
  • Argyrochaeta parviflora Cav.
  • Echetrosis pentasperma Phil.
  • Parthenium bipinnatifidum (Ortega) Rollins
  • Parthenium glomeratum Rollins
  • Parthenium hysterophorus var. hysterophorus
  • Parthenium lobatum Buckley
  • Parthenium pinnatifidum Stokes
  • Villanova bipinnatifida Ortega

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.