Asclepias verticillataL.

whorled milkweed

WFO wfo-0000551862 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Asclepias verticillata, photographed by Michelle W. （鍾偉瑋）
fig. a Michelle W. （鍾偉瑋）, CC BY 4.0 / 2022-05-22 / obs. 199924671
Asclepias verticillata, photographed by Zakqary Roy
fig. b Zakqary Roy, CC BY 4.0 / obs. 200068562
Asclepias verticillata, photographed by Michelle W. （鍾偉瑋）
fig. c Michelle W. （鍾偉瑋）, CC BY 4.0 / obs. 199925740
Asclepias verticillata, photographed by Michael J. Papay
fig. d Michael J. Papay, CC BY 4.0 / obs. 166992102
Asclepias verticillata, photographed by Yann Kemper
fig. e Yann Kemper, CC0 1.0 / obs. 156773564
Asclepias verticillata, photographed by Yann Kemper
fig. f Yann Kemper, CC0 1.0 / obs. 156777945
Asclepias verticillata, photographed by Eric Schmidt
fig. g Eric Schmidt, CC BY 4.0 / obs. 173824308
Asclepias verticillata, photographed by Jason Swanson
fig. h Jason Swanson, CC0 1.0 / obs. 154464774

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.

Confused withby our own model

These are not lookalikes we guessed at. Each one is a species our identification model genuinely mistook for this plant, and how many times. The error rate is published.

Flowering n = 1,686 observations

Peak flowering in Jul, from 1,686 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 6 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.

  • Asclepias galioides Kunth
  • Asclepias linifolia Kunth
  • Asclepias parviflora Leconte ex Decne.
  • Asclepias verticillata var. galioides (Kunth) Decne.
  • Asclepias verticillata var. leptophylla Torr.
  • Asclepias verticillata var. linifolia (Kunth) Decne.

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.