Wildflowers Blooming in Colorado in September (56 Species)

56 wildflowers were recorded blooming in Colorado in September in our iNaturalist sample; 16 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.

Mar Apr May Jun Jul Aug Sep Oct

Top wildflowers in September

Rocky Mountain Beeplant308 obs.

Rubber Rabbitbrush160 obs.

Fireweed136 obs.

Field Bindweed67 obs.

Western Harebell62 obs.

Pearly Everlasting60 obs.

Common Yarrow55 obs.

Great Mullein52 obs.

Purple Groundcherry50 obs.

Puncture Vine42 obs.

Blue Columbine39 obs.

Shrubby Cinquefoil31 obs.

All wildflowers blooming in Colorado in September

#	Species	Scientific name	Family	Obs.	Peak in state
1	Rocky Mountain Beeplant	Cleomella serrulata	Spider Flower Family	308	Aug (past peak)
2	Rubber Rabbitbrush	Ericameria nauseosa	Sunflowers, Daisies, Asters, and Allies	160	Sep (peak)
3	Fireweed	Chamaenerion angustifolium	evening primrose family	136	Jul (past peak)
4	Field Bindweed	Convolvulus arvensis	bindweed family	67	Jun (past peak)
5	Western Harebell	Campanula petiolata	bellflower family	62	Jul (past peak)
6	Pearly Everlasting	Anaphalis margaritacea	Sunflowers, Daisies, Asters, and Allies	60	Aug (past peak)
7	Common Yarrow	Achillea millefolium	Sunflowers, Daisies, Asters, and Allies	55	Jul (past peak)
8	Great Mullein	Verbascum thapsus	figwort family	52	Jul (past peak)
9	Purple Groundcherry	Quincula lobata	nightshade family	50	May (past peak)
10	Puncture Vine	Tribulus terrestris	caltrops	42	Aug (past peak)
11	Blue Columbine	Aquilegia coerulea	buttercup family	39	Jul (past peak)
12	Shrubby Cinquefoil	Dasiphora fruticosa	rose family	31	Jul (past peak)
13	Cowpen Daisy	Verbesina encelioides	Sunflowers, Daisies, Asters, and Allies	29	Sep (peak)
14	Scarlet Gilia	Ipomopsis aggregata	phlox family	28	Jul (past peak)
15	Common Toadflax	Linaria vulgaris	Plantain Family	26	Aug (past peak)
16	Alfalfa	Medicago sativa	Legumes	25	Jun (past peak)
17	Red Clover	Trifolium pratense	Legumes	24	Jul (past peak)
18	Creeping Thistle	Cirsium arvense	Sunflowers, Daisies, Asters, and Allies	22	Jul (past peak)
19	Musk Thistle	Carduus nutans	Sunflowers, Daisies, Asters, and Allies	22	Jul (past peak)
20	Curlycup Gumweed	Grindelia squarrosa	Sunflowers, Daisies, Asters, and Allies	22	Sep (peak)
21	Dwarf Mallow	Malva neglecta	Mallow and Hibiscus Family	19	Sep (peak)
22	Common Soapwort	Saponaria officinalis	pink family	17	Sep (peak)
23	Yellow Sweetclover	Melilotus officinalis	Legumes	15	Jun (past peak)
24	Common Sunflower	Helianthus annuus	Sunflowers, Daisies, Asters, and Allies	14	Aug (past peak)
25	Hoary Alyssum	Berteroa incana	mustard family	13	Aug (past peak)
26	American bistort	Bistorta bistortoides	knotweed family	13	Jul (past peak)
27	Upright Prairie Coneflower	Ratibida columnifera	Sunflowers, Daisies, Asters, and Allies	13	Jul (past peak)
28	Chicory	Cichorium intybus	Sunflowers, Daisies, Asters, and Allies	12	Aug (past peak)
29	White Sweetclover	Melilotus albus	Legumes	12	Oct (rising)
30	Redstem Stork's-bill	Erodium cicutarium	Geranium family	11	May (past peak)
31	Buffalo-Bur	Solanum rostratum	nightshade family	10	Aug (past peak)
32	Sulfur Buckwheat	Eriogonum umbellatum	knotweed family	10	Jun (past peak)
33	Winecup Mallow	Callirhoe involucrata	Mallow and Hibiscus Family	9	Jul (past peak)
34	Bull Thistle	Cirsium vulgare	Sunflowers, Daisies, Asters, and Allies	8	Sep (peak)
35	Common Tansy	Tanacetum vulgare	Sunflowers, Daisies, Asters, and Allies	8	Sep (peak)
36	Broad-Leaved Sweet Pea	Lathyrus latifolius	Legumes	8	Aug (past peak)
37	Richardson's geranium	Geranium richardsonii	Geranium family	8	Jul (past peak)
38	White Campion	Silene latifolia	pink family	8	Sep (peak)
39	Prairie Pasqueflower	Pulsatilla nuttalliana	buttercup family	8	May (past peak)
40	Common Jewelweed	Impatiens capensis	balsam family	7	Sep (peak)
41	Firewheel	Gaillardia pulchella	Sunflowers, Daisies, Asters, and Allies	7	Sep (peak)
42	Spotted Knapweed	Centaurea stoebe	Sunflowers, Daisies, Asters, and Allies	7	Sep (peak)
43	Horseweed	Erigeron canadensis	Sunflowers, Daisies, Asters, and Allies	7	Sep (peak)
44	Virginia strawberry	Fragaria virginiana	rose family	7	Jun (past peak)
45	Edible Valerian	Valeriana edulis	honeysuckle family	7	Jul (past peak)
46	Common Dandelion	Taraxacum officinale	Sunflowers, Daisies, Asters, and Allies	6	Apr (past peak)
47	White Clover	Trifolium repens	Legumes	6	Sep (peak)
48	Oxeye Daisy	Leucanthemum vulgare	Sunflowers, Daisies, Asters, and Allies	6	Sep (peak)
49	Sacred Datura	Datura wrightii	nightshade family	6	Sep (peak)
50	Wild Carrot	Daucus carota	carrot family	6	Sep (peak)