55 wildflowers were recorded blooming in Wyoming in September in our iNaturalist sample; 12 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top wildflowers in September
Fireweed
Western Harebell
Pearly Everlasting
Musk Thistle
Curlycup Gumweed
Common Yarrow
Rocky Mountain Beeplant
Rubber Rabbitbrush
Virginia strawberry
Spotted Knapweed
Shrubby Cinquefoil
Red Clover
All wildflowers blooming in Wyoming in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Fireweed | Chamaenerion angustifolium | evening primrose family | 67 | Jul (past peak) |
| 2 | Western Harebell | Campanula petiolata | bellflower family | 50 | Jul (past peak) |
| 3 | Pearly Everlasting | Anaphalis margaritacea | Sunflowers, Daisies, Asters, and Allies | 24 | Aug (past peak) |
| 4 | Musk Thistle | Carduus nutans | Sunflowers, Daisies, Asters, and Allies | 19 | Aug (past peak) |
| 5 | Curlycup Gumweed | Grindelia squarrosa | Sunflowers, Daisies, Asters, and Allies | 18 | Aug (past peak) |
| 6 | Common Yarrow | Achillea millefolium | Sunflowers, Daisies, Asters, and Allies | 16 | Aug (past peak) |
| 7 | Rocky Mountain Beeplant | Cleomella serrulata | Spider Flower Family | 16 | Aug (past peak) |
| 8 | Rubber Rabbitbrush | Ericameria nauseosa | Sunflowers, Daisies, Asters, and Allies | 15 | Sep (peak) |
| 9 | Virginia strawberry | Fragaria virginiana | rose family | 13 | Jun (past peak) |
| 10 | Spotted Knapweed | Centaurea stoebe | Sunflowers, Daisies, Asters, and Allies | 12 | Aug (past peak) |
| 11 | Shrubby Cinquefoil | Dasiphora fruticosa | rose family | 9 | Jul (past peak) |
| 12 | Red Clover | Trifolium pratense | Legumes | 8 | Jul (past peak) |
| 13 | White Campion | Silene latifolia | pink family | 8 | Sep (peak) |
| 14 | Lewis' monkeyflower | Erythranthe lewisii | lopseed family | 8 | Aug (past peak) |
| 15 | Mountain Bog Gentian | Gentiana calycosa | gentian family | 7 | Aug (past peak) |
| 16 | Yellow Sweetclover | Melilotus officinalis | Legumes | 6 | Aug (past peak) |
| 17 | Fringed Grass of Parnassus | Parnassia fimbriata | staff-vine family | 6 | Aug (past peak) |
| 18 | Scarlet Gilia | Ipomopsis aggregata | phlox family | 5 | Jul (past peak) |
| 19 | Field Bindweed | Convolvulus arvensis | bindweed family | 5 | Aug (past peak) |
| 20 | Great Mullein | Verbascum thapsus | figwort family | 5 | Jul (past peak) |
| 21 | Deptford pink | Dianthus armeria | pink family | 5 | Aug (past peak) |
| 22 | Hoary Alyssum | Berteroa incana | mustard family | 5 | Aug (past peak) |
| 23 | Yellow Salsify | Tragopogon dubius | Sunflowers, Daisies, Asters, and Allies | 4 | Jun (past peak) |
| 24 | Common Tansy | Tanacetum vulgare | Sunflowers, Daisies, Asters, and Allies | 4 | Aug (past peak) |
| 25 | Creeping Thistle | Cirsium arvense | Sunflowers, Daisies, Asters, and Allies | 4 | Aug (past peak) |
| 26 | Seep Monkeyflower | Erythranthe guttata | lopseed family | 4 | Jul (past peak) |
| 27 | White Clover | Trifolium repens | Legumes | 3 | Jul (past peak) |
| 28 | Monument Plant | Frasera speciosa | gentian family | 3 | Jul (past peak) |
| 29 | Sulfur Buckwheat | Eriogonum umbellatum | knotweed family | 3 | Jul (past peak) |
| 30 | Common Dandelion | Taraxacum officinale | Sunflowers, Daisies, Asters, and Allies | 2 | May (past peak) |
| 31 | Bull Thistle | Cirsium vulgare | Sunflowers, Daisies, Asters, and Allies | 2 | Aug (past peak) |
| 32 | Elephant's-Head lousewort | Pedicularis groenlandica | broomrape family | 2 | Jul (past peak) |
| 33 | Lewis flax | Linum lewisii | Flax Family | 2 | Jun (past peak) |
| 34 | Alsike clover | Trifolium hybridum | Legumes | 2 | Aug (past peak) |
| 35 | California poppy | Eschscholzia californica | Poppy Family | 1 | Sep (peak) |
| 36 | Common Snowberry | Symphoricarpos albus | honeysuckle family | 1 | Sep (peak) |
| 37 | Chicory | Cichorium intybus | Sunflowers, Daisies, Asters, and Allies | 1 | Aug (past peak) |
| 38 | Bittersweet Nightshade | Solanum dulcamara | nightshade family | 1 | Sep (peak) |
| 39 | Common Soapwort | Saponaria officinalis | pink family | 1 | Sep (peak) |
| 40 | Common Sunflower | Helianthus annuus | Sunflowers, Daisies, Asters, and Allies | 1 | Aug (past peak) |
| 41 | White Sweetclover | Melilotus albus | Legumes | 1 | Aug (past peak) |
| 42 | Sulphur Cinquefoil | Potentilla recta | rose family | 1 | Sep (peak) |
| 43 | Pipsissewa | Chimaphila umbellata | heath family | 1 | Jul (past peak) |
| 44 | Arrowleaf Balsamroot | Balsamorhiza sagittata | Sunflowers, Daisies, Asters, and Allies | 1 | Jun (past peak) |
| 45 | black-eyed Susan | Rudbeckia hirta | Sunflowers, Daisies, Asters, and Allies | 1 | Sep (peak) |
| 46 | Puncture Vine | Tribulus terrestris | caltrops | 1 | Sep (peak) |
| 47 | American bistort | Bistorta bistortoides | knotweed family | 1 | Jun (past peak) |
| 48 | Common Sneezeweed | Helenium autumnale | Sunflowers, Daisies, Asters, and Allies | 1 | Sep (peak) |
| 49 | Flower-Of-An-Hour | Hibiscus trionum | Mallow and Hibiscus Family | 1 | Sep (peak) |
| 50 | Dwarf Mallow | Malva neglecta | Mallow and Hibiscus Family | 1 | Sep (peak) |