Quick answer: 14 native Montana plants have a recorded bloom range that includes October.
14 species
- Big bluestem Andropogon gerardii · 25 states
- Black-eyed Susan Rudbeckia hirta · 42 states
- Blue grama Bouteloua gracilis · 15 states
- Buffalograss Bouteloua dactyloides · 9 states
- Cutleaf coneflower Rudbeckia laciniata · 21 states
- Dotted blazing star Liatris punctata · 10 states
- Indiangrass Sorghastrum nutans · 19 states
- Little bluestem Schizachyrium scoparium · 23 states
- Mexican hat Ratibida columnifera · 17 states
- Pearly everlasting Anaphalis margaritacea · 18 states
- Scarlet gilia Ipomopsis aggregata · 9 states
- Sideoats grama Bouteloua curtipendula · 25 states
- Swamp milkweed Asclepias incarnata · 25 states
- Switchgrass Panicum virgatum · 24 states