Penstemon procerus (Slender Penstemon)

Plate 1 figs. a–h · 8 separate observations

Penstemon procerus, photographed by Braden J. Judson — fig. a Braden J. Judson, CC0 1.0 / 2022-06-06 / obs. 205926008

Penstemon procerus, photographed by Shane Johnson — fig. b Shane Johnson, CC0 1.0 / obs. 204634102

Penstemon procerus, photographed by Allison Gray — fig. c Allison Gray, CC BY 4.0 / obs. 161175492

Penstemon procerus, photographed by Joseph Rojas — fig. d Joseph Rojas, CC BY 4.0 / obs. 151815331

Penstemon procerus, photographed by Trevor Van Loon — fig. e Trevor Van Loon, CC BY 4.0 / obs. 151665044

Penstemon procerus, photographed by John Brew — fig. f John Brew, CC BY 4.0 / obs. 145869630

Penstemon procerus, photographed by Paul McClellan — fig. h Paul McClellan, CC BY 4.0 / obs. 145764535

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.

Native range 16 botanical countries

Native distribution of Penstemon procerus, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows.

Region	TDWG code	Continent
Alaska	ASK	NORTHERN AMERICA
Alberta	ABT
British Columbia	BRC
California	CAL
Colorado	COL
Idaho	IDA
Manitoba	MAN
Montana	MNT
Nevada	NEV
North Dakota	NDA
Oregon	ORE
Saskatchewan	SAS
Utah	UTA
Washington	WAS
Wyoming	WYO
Yukon	YUK

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Flowering 513 in flower of 606 examined

56%

93%

95%

85%

36%

21%

Proportion of examined Penstemon procerus in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	0	too few examined
Feb	0	0	too few examined
Mar	0	1	too few examined
Apr	0	2	too few examined
May	28	50	56%	42% to 69%
Jun	197	212	93%	89% to 96%
Jul	207	219	95%	91% to 97%
Aug	68	80	85%	76% to 91%
Sep	10	28	36%	21% to 54%
Oct	3	14	21%	8% to 48%
Nov	0	0	too few examined
Dec	0	0	too few examined

Peak flowering in Jul. Each bar is the share of Penstemon procerus 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. 513 of 606 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 6 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 30 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.

Lepteiris parviflora Raf.
Penstemon brachyanthus Pennell
Penstemon cacuminis Pennell
Penstemon confertus var. aberrans M.E.Jones
Penstemon confertus var. modestus (Greene) Jeps.
Penstemon confertus var. procerus (Douglas ex Graham) Coville
Penstemon formosus A.Nelson
Penstemon micranthus Nutt.
Penstemon modestus Greene
Penstemon pononii Anon.
Penstemon procerus f. albescens B.Boivin
Penstemon procerus f. jenkinsii B.Boivin
Penstemon procerus f. procerus
Penstemon procerus subsp. aberrans (M.E.Jones) D.D.Keck
Penstemon procerus subsp. brachyanthus (Pennell) D.D.Keck
Penstemon procerus subsp. formosus (D.D.Keck) D.D.Keck
Penstemon procerus subsp. modestus (Greene) D.D.Keck
Penstemon procerus subsp. pulvereus Pennell
Penstemon procerus subsp. tolmiei (Hook.) D.D.Keck
Penstemon procerus subsp. typicus D.D.Keck
Penstemon procerus var. fimbriatus Regel
Penstemon procerus var. micrantus (Nutt.) M.E.Jones
Penstemon pulchellus Greene
Penstemon spicatus Anon.

and 6 more.

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.
Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

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.