60 wildflowers were recorded blooming in New Jersey in May in our iNaturalist sample; 42 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top wildflowers in May

Pink Lady's Slipper
common star-of-Bethlehem

Mountain Laurel

Philadelphia fleabane

Sheep Laurel

Red Columbine

Northern Starflower

Multiflora Rose
Wild Geranium
Virginia Springbeauty

White Clover

Ground-Ivy
All wildflowers blooming in New Jersey in May
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Pink Lady's Slipper | Cypripedium acaule | Orchids | 510 | May (peak) |
| 2 | common star-of-Bethlehem | Ornithogalum umbellatum | agave and allies | 279 | May (peak) |
| 3 | Mountain Laurel | Kalmia latifolia | heath family | 231 | May (peak) |
| 4 | Philadelphia fleabane | Erigeron philadelphicus | Sunflowers, Daisies, Asters, and Allies | 179 | May (peak) |
| 5 | Sheep Laurel | Kalmia angustifolia | heath family | 168 | May (peak) |
| 6 | Red Columbine | Aquilegia canadensis | buttercup family | 160 | May (peak) |
| 7 | Northern Starflower | Lysimachia borealis | primrose family | 155 | May (peak) |
| 8 | Multiflora Rose | Rosa multiflora | rose family | 154 | May (peak) |
| 9 | Wild Geranium | Geranium maculatum | Geranium family | 142 | May (peak) |
| 10 | Virginia Springbeauty | Claytonia virginica | Pussypaw Family | 141 | Apr (past peak) |
| 11 | White Clover | Trifolium repens | Legumes | 138 | May (peak) |
| 12 | Ground-Ivy | Glechoma hederacea | Mint Family | 124 | Apr (past peak) |
| 13 | Catchweed Bedstraw | Galium aparine | madder family | 119 | May (peak) |
| 14 | Beach Plum | Prunus maritima | rose family | 116 | May (peak) |
| 15 | Canada toadflax | Linaria canadensis | Plantain Family | 112 | May (peak) |
| 16 | Red Deadnettle | Lamium purpureum | Mint Family | 109 | Apr (past peak) |
| 17 | Garlic Mustard | Alliaria petiolata | mustard family | 105 | Apr (past peak) |
| 18 | Jack-in-the-Pulpit | Arisaema triphyllum | Arum Family | 104 | May (peak) |
| 19 | Partridgeberry | Mitchella repens | madder family | 104 | Jun (rising) |
| 20 | Mock Strawberry | Potentilla indica | rose family | 94 | May (peak) |
| 21 | Narrow-Leaved Bittercress | Cardamine impatiens | mustard family | 93 | May (peak) |
| 22 | Dame's Rocket | Hesperis matronalis | mustard family | 91 | May (peak) |
| 23 | American tuliptree | Liriodendron tulipifera | magnolia family | 91 | May (peak) |
| 24 | Canada mayflower | Maianthemum canadense | agave and allies | 85 | May (peak) |
| 25 | Autumn Olive | Elaeagnus umbellata | oleaster family | 80 | May (peak) |
| 26 | Bristle Thistle | Cirsium horridulum | Sunflowers, Daisies, Asters, and Allies | 73 | May (peak) |
| 27 | Yellow Iris | Iris pseudacorus | iris family | 72 | May (peak) |
| 28 | Black Medick | Medicago lupulina | Legumes | 71 | May (peak) |
| 29 | Black Cherry | Prunus serotina | rose family | 67 | May (peak) |
| 30 | Flowering Dogwood | Cornus florida | Dogwood family | 63 | May (peak) |
| 31 | Amur honeysuckle | Lonicera maackii | honeysuckle family | 61 | May (peak) |
| 32 | Rue Anemone | Thalictrum thalictroides | buttercup family | 61 | Apr (past peak) |
| 33 | White Campion | Silene latifolia | pink family | 60 | May (peak) |
| 34 | European lily of the valley | Convallaria majalis | agave and allies | 59 | May (peak) |
| 35 | Mayapple | Podophyllum peltatum | barberry family | 59 | May (peak) |
| 36 | Fringed Polygala | Polygaloides paucifolia | milkworts | 57 | May (peak) |
| 37 | Purple Pitcher Plant | Sarracenia purpurea | New World pitcher plants | 51 | May (peak) |
| 38 | Red Clover | Trifolium pratense | Legumes | 50 | Jun (rising) |
| 39 | Deerberry | Vaccinium stamineum | heath family | 50 | May (peak) |
| 40 | Greater celandine | Chelidonium majus | Poppy Family | 49 | May (peak) |
| 41 | Dwarf Ginseng | Panax trifolius | ivy family | 49 | Apr (past peak) |
| 42 | Azure Bluet | Houstonia caerulea | madder family | 48 | May (peak) |
| 43 | Ribwort Plantain | Plantago lanceolata | Plantain Family | 47 | May (peak) |
| 44 | American bladdernut | Staphylea trifolia | bladdernut family | 46 | May (peak) |
| 45 | Carpet Bugle | Ajuga reptans | Mint Family | 45 | May (peak) |
| 46 | Northern Blue Flag | Iris versicolor | iris family | 44 | May (peak) |
| 47 | Black Locust | Robinia pseudoacacia | Legumes | 44 | May (peak) |
| 48 | Tall Blue Wild Indigo | Baptisia australis | Legumes | 44 | May (peak) |
| 49 | Blackhaw | Viburnum prunifolium | elder family | 44 | May (peak) |
| 50 | Thyme-Leaved Speedwell | Veronica serpyllifolia | Plantain Family | 43 | May (peak) |