Symphyotrichum concolor (eastern silver aster)

Plate 1 figs. a–h · 8 separate observations

Symphyotrichum concolor, photographed by mark-groeneveld — fig. a mark-groeneveld, CC BY 4.0 / 2021-12-16 / obs. 172908938

Symphyotrichum concolor, photographed by Darren Oh — fig. b Darren Oh, CC BY-SA 4.0 / obs. 170137064

Symphyotrichum concolor, photographed by Lyn Roueche — fig. c Lyn Roueche, CC0 1.0 / obs. 169347824

Symphyotrichum concolor, photographed by Lauren McLaurin — fig. d Lauren McLaurin, CC BY 4.0 / obs. 165095284

Symphyotrichum concolor, photographed by Chase Mathey — fig. e Chase Mathey, CC BY 4.0 / obs. 157422598

Symphyotrichum concolor, photographed by Valerie Anderson — fig. f Valerie Anderson, CC BY 4.0 / obs. 107813077

Symphyotrichum concolor, photographed by Alan Weakley — fig. g Alan Weakley, CC0 1.0 / obs. 88092572

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 17 botanical countries

Native distribution of Symphyotrichum concolor, 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. Regions too small to draw at this scale are marked with a dot.

Region	TDWG code	Continent
Alabama	ALA	NORTHERN AMERICA
Delaware	DEL
Florida	FLA
Georgia	GEO
Kentucky	KTY
Louisiana	LOU
Maryland	MRY
Massachusetts	MAS
Mississippi	MSI
New Jersey	NWJ
New York	NWY
North Carolina	NCA
Rhode I.	RHO
South Carolina	SCA
Tennessee	TEN
Virginia	VRG
Bahamas	BAH	SOUTHERN AMERICA

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 163 in flower of 174 examined

100%

56%

97%

94%

Proportion of examined Symphyotrichum concolor in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	2	2	too few examined
Feb	1	1	too few examined
Mar	0	0	too few examined
Apr	4	4	too few examined
May	10	10	100%	72% to 100%
Jun	0	0	too few examined
Jul	0	2	too few examined
Aug	0	0	too few examined
Sep	5	9	56%	27% to 81%
Oct	67	69	97%	90% to 99%
Nov	59	61	97%	89% to 99%
Dec	15	16	94%	72% to 99%

Peak flowering in May. Each bar is the share of Symphyotrichum concolor 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. 163 of 174 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 7 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.

Where it actually grows measured, from 630 observations

Condition	5th percentile	Median	95th percentile
Coldest month, mean daily low	-0.3 °C	6.5 °C	14.2 °C
Warmest month, mean daily high	29.4 °C	31.6 °C	32.6 °C
Annual rainfall	1,169 mm	1,378 mm	1,806 mm
Rainfall in the driest quarter	135 mm	256 mm	361 mm

It is found where winters bring light frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 630 research-grade observations of Symphyotrichum concolor that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 11 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.

Aster concolor L.
Aster concolor f. concolor
Aster concolor f. lasiocaulis Fernald
Aster concolor var. concolor
Aster concolor var. devestitus S.F.Blake
Aster concolor var. simulatus (Small) R.W.Long
Aster simulatus Small
Lasallea concolor (L.) Semple & Brouillet
Symphyotrichum concolor subsp. devestitum (S.F.Blake) A.Haines
Symphyotrichum concolor var. concolor
Virgulus concolor (L.) Reveal & Keener

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.