60 wildflowers were recorded blooming in New Jersey in September in our iNaturalist sample; 27 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top wildflowers in September

White Snakeroot

Common Jewelweed

Late Boneset
Purple Loosestrife

Asiatic dayflower
Groundsel Tree

White Wood Aster

black-eyed Susan

Autumn Clematis
Chicory

New England aster

Ghost Pipe
All wildflowers blooming in New Jersey in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | White Snakeroot | Ageratina altissima | Sunflowers, Daisies, Asters, and Allies | 250 | Sep (peak) |
| 2 | Common Jewelweed | Impatiens capensis | balsam family | 145 | Sep (peak) |
| 3 | Late Boneset | Eupatorium serotinum | Sunflowers, Daisies, Asters, and Allies | 101 | Sep (peak) |
| 4 | Purple Loosestrife | Lythrum salicaria | lythrum family | 93 | Aug (past peak) |
| 5 | Asiatic dayflower | Commelina communis | Spiderworts | 90 | Sep (peak) |
| 6 | Groundsel Tree | Baccharis halimifolia | Sunflowers, Daisies, Asters, and Allies | 82 | Sep (peak) |
| 7 | White Wood Aster | Eurybia divaricata | Sunflowers, Daisies, Asters, and Allies | 71 | Sep (peak) |
| 8 | black-eyed Susan | Rudbeckia hirta | Sunflowers, Daisies, Asters, and Allies | 68 | Jul (past peak) |
| 9 | Autumn Clematis | Clematis terniflora | buttercup family | 68 | Sep (peak) |
| 10 | Chicory | Cichorium intybus | Sunflowers, Daisies, Asters, and Allies | 61 | Jul (past peak) |
| 11 | New England aster | Symphyotrichum novae-angliae | Sunflowers, Daisies, Asters, and Allies | 61 | Sep (peak) |
| 12 | Ghost Pipe | Monotropa uniflora | heath family | 53 | Jul (past peak) |
| 13 | Northern Seaside Goldenrod | Solidago sempervirens | Sunflowers, Daisies, Asters, and Allies | 53 | Oct (rising) |
| 14 | Flat-Topped Goldenrod | Euthamia graminifolia | Sunflowers, Daisies, Asters, and Allies | 52 | Sep (peak) |
| 15 | Climbing Hempvine | Mikania scandens | Sunflowers, Daisies, Asters, and Allies | 50 | Sep (peak) |
| 16 | Marsh Fleabane | Pluchea odorata | Sunflowers, Daisies, Asters, and Allies | 47 | Sep (peak) |
| 17 | American hog-peanut | Amphicarpaea bracteata | Legumes | 45 | Sep (peak) |
| 18 | Blue Mistflower | Conoclinium coelestinum | Sunflowers, Daisies, Asters, and Allies | 42 | Sep (peak) |
| 19 | Blue Curls | Trichostema dichotomum | Mint Family | 41 | Sep (peak) |
| 20 | Pinesap | Monotropa hypopitys | heath family | 37 | Sep (peak) |
| 21 | White Clover | Trifolium repens | Legumes | 34 | May (past peak) |
| 22 | Common Sneezeweed | Helenium autumnale | Sunflowers, Daisies, Asters, and Allies | 34 | Sep (peak) |
| 23 | Common Toadflax | Linaria vulgaris | Plantain Family | 33 | Sep (peak) |
| 24 | Red Clover | Trifolium pratense | Legumes | 33 | Jun (past peak) |
| 25 | Nodding Beggarticks | Bidens cernua | Sunflowers, Daisies, Asters, and Allies | 33 | Sep (peak) |
| 26 | Common Wrinkle-Leaved Goldenrod | Solidago rugosa | Sunflowers, Daisies, Asters, and Allies | 33 | Sep (peak) |
| 27 | Arrow-Leaved Tearthumb | Persicaria sagittata | knotweed family | 33 | Sep (peak) |
| 28 | Wild Carrot | Daucus carota | carrot family | 32 | Jul (past peak) |
| 29 | Japanese honeysuckle | Lonicera japonica | honeysuckle family | 31 | Jun (past peak) |
| 30 | brown-eyed Susan | Rudbeckia triloba | Sunflowers, Daisies, Asters, and Allies | 31 | Aug (past peak) |
| 31 | Common Boneset | Eupatorium perfoliatum | Sunflowers, Daisies, Asters, and Allies | 29 | Aug (past peak) |
| 32 | Low Smartweed | Persicaria longiseta | knotweed family | 28 | Oct (rising) |
| 33 | American trumpet vine | Campsis radicans | bignonia family | 27 | Aug (past peak) |
| 34 | Great Blue Lobelia | Lobelia siphilitica | bellflower family | 27 | Aug (past peak) |
| 35 | Sweet Everlasting | Pseudognaphalium obtusifolium | Sunflowers, Daisies, Asters, and Allies | 27 | Sep (peak) |
| 36 | Bird's-Foot Trefoil | Lotus corniculatus | Legumes | 26 | Jun (past peak) |
| 37 | White Turtlehead | Chelone glabra | Plantain Family | 25 | Sep (peak) |
| 38 | Cutleaf Coneflower | Rudbeckia laciniata | Sunflowers, Daisies, Asters, and Allies | 25 | Aug (past peak) |
| 39 | Common Hibiscus | Hibiscus syriacus | Mallow and Hibiscus Family | 25 | Jul (past peak) |
| 40 | American burnweed | Erechtites hieraciifolius | Sunflowers, Daisies, Asters, and Allies | 25 | Sep (peak) |
| 41 | Pickerelweed | Pontederia cordata | Pickerelweeds | 24 | Jul (past peak) |
| 42 | Common Selfheal | Prunella vulgaris | Mint Family | 24 | Jul (past peak) |
| 43 | Swamp Rose Mallow | Hibiscus moscheutos | Mallow and Hibiscus Family | 23 | Aug (past peak) |
| 44 | Citronella Horse Balm | Collinsonia canadensis | Mint Family | 23 | Sep (peak) |
| 45 | Porcelain Berry | Ampelopsis glandulosa | Grape Family | 23 | Aug (past peak) |
| 46 | Bull Thistle | Cirsium vulgare | Sunflowers, Daisies, Asters, and Allies | 22 | Aug (past peak) |
| 47 | False Daisy | Eclipta prostrata | Sunflowers, Daisies, Asters, and Allies | 22 | Sep (peak) |
| 48 | Obedient Plant | Physostegia virginiana | Mint Family | 22 | Sep (peak) |
| 49 | Wingstem | Verbesina alternifolia | Sunflowers, Daisies, Asters, and Allies | 22 | Sep (peak) |
| 50 | Cardinal Flower | Lobelia cardinalis | bellflower family | 21 | Aug (past peak) |