Quick answer: 19 native Connecticut plants have a recorded bloom range that includes October.
19 species
- Big bluestem Andropogon gerardii · 25 states
- Black-eyed Susan Rudbeckia hirta · 42 states
- Blue mistflower Conoclinium coelestinum · 26 states
- Canadian burnet Sanguisorba canadensis · 1 states
- Cardinal flower Lobelia cardinalis · 37 states
- Closed bottle gentian Gentiana andrewsii · 10 states
- Common sneezeweed Helenium autumnale · 13 states
- Cutleaf coneflower Rudbeckia laciniata · 21 states
- Great blue lobelia Lobelia siphilitica · 32 states
- Little bluestem Schizachyrium scoparium · 23 states
- New England aster Symphyotrichum novae-angliae · 18 states
- Northern bayberry Morella pensylvanica · 2 states
- Partridgeberry Mitchella repens · 17 states
- Pearly everlasting Anaphalis margaritacea · 18 states
- Scarlet beebalm Monarda didyma · 18 states
- Seaside goldenrod Solidago sempervirens · 2 states
- Spotted beebalm Monarda punctata · 14 states
- Switchgrass Panicum virgatum · 24 states
- Witch-hazel Hamamelis virginiana · 28 states