60 wildflowers were recorded blooming in Wisconsin in October in our iNaturalist sample; 3 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top wildflowers in October

New England aster

White Snakeroot

Large-Leaved Aster

American Witch-Hazel

Common Toadflax

Red Clover
Fall Phlox

brown-eyed Susan
Chicory

Hoary Alyssum

Frost Aster

Spotted Knapweed
All wildflowers blooming in Wisconsin in October
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | New England aster | Symphyotrichum novae-angliae | Sunflowers, Daisies, Asters, and Allies | 92 | Sep (past peak) |
| 2 | White Snakeroot | Ageratina altissima | Sunflowers, Daisies, Asters, and Allies | 43 | Sep (past peak) |
| 3 | Large-Leaved Aster | Eurybia macrophylla | Sunflowers, Daisies, Asters, and Allies | 43 | Aug (past peak) |
| 4 | American Witch-Hazel | Hamamelis virginiana | witch-hazel family | 30 | Oct (peak) |
| 5 | Common Toadflax | Linaria vulgaris | Plantain Family | 25 | Aug (past peak) |
| 6 | Red Clover | Trifolium pratense | Legumes | 25 | Jun (past peak) |
| 7 | Fall Phlox | Phlox paniculata | phlox family | 25 | Oct (peak) |
| 8 | brown-eyed Susan | Rudbeckia triloba | Sunflowers, Daisies, Asters, and Allies | 21 | Aug (past peak) |
| 9 | Chicory | Cichorium intybus | Sunflowers, Daisies, Asters, and Allies | 18 | Jul (past peak) |
| 10 | Hoary Alyssum | Berteroa incana | mustard family | 18 | Jul (past peak) |
| 11 | Frost Aster | Symphyotrichum pilosum | Sunflowers, Daisies, Asters, and Allies | 18 | Sep (past peak) |
| 12 | Spotted Knapweed | Centaurea stoebe | Sunflowers, Daisies, Asters, and Allies | 15 | Jul (past peak) |
| 13 | Wild Carrot | Daucus carota | carrot family | 15 | Jul (past peak) |
| 14 | Shaggy Soldier | Galinsoga quadriradiata | Sunflowers, Daisies, Asters, and Allies | 14 | Oct (peak) |
| 15 | black-eyed Susan | Rudbeckia hirta | Sunflowers, Daisies, Asters, and Allies | 13 | Jul (past peak) |
| 16 | Marsh Marigold | Caltha palustris | buttercup family | 12 | May (past peak) |
| 17 | White Campion | Silene latifolia | pink family | 12 | Jun (past peak) |
| 18 | Broad-Leaved Goldenrod | Solidago flexicaulis | Sunflowers, Daisies, Asters, and Allies | 11 | Sep (past peak) |
| 19 | Common Jewelweed | Impatiens capensis | balsam family | 8 | Aug (past peak) |
| 20 | Asiatic dayflower | Commelina communis | Spiderworts | 8 | Aug (past peak) |
| 21 | Calico Aster | Symphyotrichum lateriflorum | Sunflowers, Daisies, Asters, and Allies | 8 | Sep (past peak) |
| 22 | Common Yarrow | Achillea millefolium | Sunflowers, Daisies, Asters, and Allies | 7 | Jun (past peak) |
| 23 | White Clover | Trifolium repens | Legumes | 7 | Jun (past peak) |
| 24 | Common Soapwort | Saponaria officinalis | pink family | 7 | Jul (past peak) |
| 25 | Common Sneezeweed | Helenium autumnale | Sunflowers, Daisies, Asters, and Allies | 7 | Sep (past peak) |
| 26 | fen grass of Parnassus | Parnassia glauca | staff-vine family | 7 | Sep (past peak) |
| 27 | Creeping Bellflower | Campanula rapunculoides | bellflower family | 6 | Jul (past peak) |
| 28 | Spotted Horsemint | Monarda punctata | Mint Family | 6 | Aug (past peak) |
| 29 | False Sunflower | Heliopsis helianthoides | Sunflowers, Daisies, Asters, and Allies | 6 | Jul (past peak) |
| 30 | Eastern Black Nightshade | Solanum emulans | nightshade family | 6 | Sep (past peak) |
| 31 | American pokeweed | Phytolacca americana | Pokeweed Family | 5 | Aug (past peak) |
| 32 | White Sweetclover | Melilotus albus | Legumes | 5 | Jul (past peak) |
| 33 | Obedient Plant | Physostegia virginiana | Mint Family | 5 | Aug (past peak) |
| 34 | Great Blue Lobelia | Lobelia siphilitica | bellflower family | 5 | Aug (past peak) |
| 35 | Purple Crownvetch | Securigera varia | Legumes | 5 | Jun (past peak) |
| 36 | Common Selfheal | Prunella vulgaris | Mint Family | 4 | Jul (past peak) |
| 37 | Pearly Everlasting | Anaphalis margaritacea | Sunflowers, Daisies, Asters, and Allies | 4 | Aug (past peak) |
| 38 | Bull Thistle | Cirsium vulgare | Sunflowers, Daisies, Asters, and Allies | 4 | Aug (past peak) |
| 39 | Common Tansy | Tanacetum vulgare | Sunflowers, Daisies, Asters, and Allies | 4 | Aug (past peak) |
| 40 | False Rue Anemone | Enemion biternatum | buttercup family | 4 | May (past peak) |
| 41 | Tall Bellflower | Campanulastrum americanum | bellflower family | 4 | Jul (past peak) |
| 42 | Orange Hawkweed | Pilosella aurantiaca | Sunflowers, Daisies, Asters, and Allies | 4 | Jun (past peak) |
| 43 | Cardinal Flower | Lobelia cardinalis | bellflower family | 3 | Aug (past peak) |
| 44 | Purple Coneflower | Echinacea purpurea | Sunflowers, Daisies, Asters, and Allies | 3 | Jul (past peak) |
| 45 | Common Groundsel | Senecio vulgaris | Sunflowers, Daisies, Asters, and Allies | 3 | Apr (past peak) |
| 46 | Bladder Campion | Silene vulgaris | pink family | 3 | Jun (past peak) |
| 47 | Hairy Vetch | Vicia villosa | Legumes | 3 | Jun (past peak) |
| 48 | Great Mullein | Verbascum thapsus | figwort family | 3 | Jul (past peak) |
| 49 | Common Evening-Primrose | Oenothera biennis | evening primrose family | 3 | Aug (past peak) |
| 50 | Tall Goldenrod | Solidago altissima | Sunflowers, Daisies, Asters, and Allies | 3 | Sep (past peak) |