60 wildflowers were recorded blooming in Pennsylvania in March in our iNaturalist sample; 8 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top wildflowers in March

Lesser Celandine

Bloodroot
Virginia Springbeauty

Eastern Skunk Cabbage
Common Snowdrop

Colt's-Foot

Hairy Bittercress

Bird's-Eye Speedwell

Red Deadnettle

Round-Lobed Hepatica

Northern Spicebush

Dutchman's breeches
All wildflowers blooming in Pennsylvania in March
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Lesser Celandine | Ficaria verna | buttercup family | 777 | Apr (rising) |
| 2 | Bloodroot | Sanguinaria canadensis | Poppy Family | 508 | Apr (rising) |
| 3 | Virginia Springbeauty | Claytonia virginica | Pussypaw Family | 381 | Apr (rising) |
| 4 | Eastern Skunk Cabbage | Symplocarpus foetidus | Arum Family | 269 | Mar (peak) |
| 5 | Common Snowdrop | Galanthus nivalis | amaryllis, onions, and allies | 232 | Mar (peak) |
| 6 | Colt's-Foot | Tussilago farfara | Sunflowers, Daisies, Asters, and Allies | 183 | Apr (rising) |
| 7 | Hairy Bittercress | Cardamine hirsuta | mustard family | 167 | Mar (peak) |
| 8 | Bird's-Eye Speedwell | Veronica persica | Plantain Family | 154 | Apr (rising) |
| 9 | Red Deadnettle | Lamium purpureum | Mint Family | 144 | Apr (rising) |
| 10 | Round-Lobed Hepatica | Hepatica americana | buttercup family | 143 | Apr (rising) |
| 11 | Northern Spicebush | Lindera benzoin | laurels | 137 | Apr (rising) |
| 12 | Dutchman's breeches | Dicentra cucullaria | Poppy Family | 125 | Apr (rising) |
| 13 | Snow Trillium | Trillium nivale | Herb-Paris, False Hellebores, Trilliums and allies | 123 | Mar (peak) |
| 14 | Carolina Springbeauty | Claytonia caroliniana | Pussypaw Family | 106 | Apr (rising) |
| 15 | Lesser Periwinkle | Vinca minor | Dogbane Family | 93 | Apr (rising) |
| 16 | Harbinger of Spring | Erigenia bulbosa | carrot family | 80 | Mar (peak) |
| 17 | Ground-Ivy | Glechoma hederacea | Mint Family | 68 | Apr (rising) |
| 18 | Siberian squill | Scilla siberica | agave and allies | 58 | Apr (rising) |
| 19 | Cut-Leaved Toothwort | Cardamine concatenata | mustard family | 53 | Apr (rising) |
| 20 | Virginia bluebells | Mertensia virginica | borage family | 50 | Apr (rising) |
| 21 | Common Whitlowgrass | Draba verna | mustard family | 46 | Mar (peak) |
| 22 | Red Maple | Acer rubrum | soapberry family | 41 | Mar (peak) |
| 23 | Yellow Trout Lily | Erythronium americanum | lily family | 40 | Apr (rising) |
| 24 | Henbit Deadnettle | Lamium amplexicaule | Mint Family | 29 | Apr (rising) |
| 25 | Sharp-Lobed Hepatica | Hepatica acutiloba | buttercup family | 23 | Apr (rising) |
| 26 | Common Groundsel | Senecio vulgaris | Sunflowers, Daisies, Asters, and Allies | 22 | Apr (rising) |
| 27 | Trailing Arbutus | Epigaea repens | heath family | 22 | Apr (rising) |
| 28 | Marsh Marigold | Caltha palustris | buttercup family | 21 | Apr (rising) |
| 29 | Rue Anemone | Thalictrum thalictroides | buttercup family | 19 | Apr (rising) |
| 30 | Common Chickweed | Stellaria media | pink family | 18 | Apr (rising) |
| 31 | Box Elder | Acer negundo | soapberry family | 17 | Apr (rising) |
| 32 | Callery pear | Pyrus calleryana | rose family | 16 | Apr (rising) |
| 33 | Early Blue Cohosh | Caulophyllum giganteum | barberry family | 16 | Apr (rising) |
| 34 | Virginia saxifrage | Micranthes virginiensis | saxifrage family | 16 | Apr (rising) |
| 35 | Redstem Stork's-bill | Erodium cicutarium | Geranium family | 12 | Mar (peak) |
| 36 | European field pansy | Viola arvensis | Violet Family | 10 | May (rising) |
| 37 | Azure Bluet | Houstonia caerulea | madder family | 10 | Apr (rising) |
| 38 | Field Penny-Cress | Thlaspi arvense | mustard family | 10 | Apr (rising) |
| 39 | Incised Fumewort | Corydalis incisa | Poppy Family | 10 | Apr (rising) |
| 40 | Eastern Leatherwood | Dirca palustris | Stringbarks | 8 | Apr (rising) |
| 41 | Lawn daisy | Bellis perennis | Sunflowers, Daisies, Asters, and Allies | 8 | May (rising) |
| 42 | Squirrel Corn | Dicentra canadensis | Poppy Family | 7 | Apr (rising) |
| 43 | Moss Phlox | Phlox subulata | phlox family | 7 | Apr (rising) |
| 44 | Common Dandelion | Taraxacum officinale | Sunflowers, Daisies, Asters, and Allies | 5 | Apr (rising) |
| 45 | Shepherd's-Purse | Capsella bursa-pastoris | mustard family | 5 | Apr (rising) |
| 46 | Yellow Corydalis | Corydalis flavula | Poppy Family | 5 | Apr (rising) |
| 47 | Halberd-leaved violet | Viola hastata | Violet Family | 5 | Apr (rising) |
| 48 | Red Trillium | Trillium erectum | Herb-Paris, False Hellebores, Trilliums and allies | 4 | Apr (rising) |
| 49 | Smooth Yellow Violet | Viola eriocarpa | Violet Family | 4 | Apr (rising) |
| 50 | American Witch-Hazel | Hamamelis virginiana | witch-hazel family | 3 | Oct (rising) |