Quick answer: 18 native Pennsylvania plants have a recorded bloom range that includes October.
18 species
- Balsam fir Abies balsamea · 2 states
- Big bluestem Andropogon gerardii · 25 states
- Black-eyed Susan Rudbeckia hirta · 42 states
- Blue mistflower Conoclinium coelestinum · 26 states
- Brown-eyed Susan Rudbeckia triloba · 6 states
- Cardinal flower Lobelia cardinalis · 37 states
- Cutleaf coneflower Rudbeckia laciniata · 21 states
- Great blue lobelia Lobelia siphilitica · 32 states
- Indiangrass Sorghastrum nutans · 19 states
- Jerusalem artichoke Helianthus tuberosus · 9 states
- Little bluestem Schizachyrium scoparium · 23 states
- New England aster Symphyotrichum novae-angliae · 18 states
- Partridgeberry Mitchella repens · 17 states
- Pearly everlasting Anaphalis margaritacea · 18 states
- Scarlet beebalm Monarda didyma · 18 states
- Sideoats grama Bouteloua curtipendula · 25 states
- Switchgrass Panicum virgatum · 24 states
- White heath aster Symphyotrichum ericoides var. ericoides · 10 states