Funastrum hirtellum (hairy milkweed)

Plate 1 figs. a–h · 8 separate observations

Funastrum hirtellum, photographed by ant, like the bug — fig. a ant, like the bug, CC0 1.0 / 2022-04-15 / obs. 188406273

Funastrum hirtellum, photographed by Ellen C Lovelidge — fig. b Ellen C Lovelidge, CC0 1.0 / obs. 186826519

Funastrum hirtellum, photographed by Trevor Van Loon — fig. c Trevor Van Loon, CC BY 4.0 / obs. 180458171

Funastrum hirtellum, photographed by Diego Blanco — fig. d Diego Blanco, CC0 1.0 / obs. 131821551

Funastrum hirtellum, photographed by Craig Martin — fig. e Craig Martin, CC0 1.0 / obs. 173919570

Funastrum hirtellum, photographed by Jim Riley — fig. f Jim Riley, CC0 1.0 / obs. 119447701

Funastrum hirtellum, photographed by Diana — fig. g Diana, CC BY 4.0 / obs. 118333475

Funastrum hirtellum, photographed by rockybajada — fig. h rockybajada, CC0 1.0 / obs. 63075066

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 292 in flower of 381 examined

55%

85%

94%

83%

75%

63%

64%

Proportion of examined Funastrum hirtellum in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	21	38	55%	40% to 70%
Feb	50	59	85%	73% to 92%
Mar	87	93	94%	87% to 97%
Apr	48	58	83%	71% to 90%
May	12	16	75%	51% to 90%
Jun	0	0	too few examined
Jul	0	1	too few examined
Aug	2	3	too few examined
Sep	10	16	63%	39% to 82%
Oct	10	16	63%	39% to 82%
Nov	14	22	64%	43% to 80%
Dec	38	59	64%	52% to 75%

Peak flowering in Mar. Each bar is the share of Funastrum hirtellum observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 292 of 381 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 3 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Also published as 4 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.

Philibertia heterophylla var. hirtella A.Gray
Philibertia hirtella (A.Gray) Parish
Sarcostemma heterophyllum var. hirtellum A.Gray
Sarcostemma hirtellum (A.Gray) R.Holm

Sourcesevery claim on this page

World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
USDA PLANTS Database. common name, checklist symbol FUHI. public domain. Retrieved 2026-07-13.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite. It has no native range either: Kew's checklist does not cover this taxon.