Quick answer: 34 native Colorado plants have a recorded bloom range that includes June.
34 species
- American plum Prunus americana · 25 states
- Apache plume Fallugia paradoxa · 6 states
- Aspen fleabane Erigeron speciosus · 3 states
- Banana yucca Yucca baccata · 6 states
- Bearberry Arctostaphylos uva-ursi · 16 states
- Black-eyed Susan Rudbeckia hirta · 42 states
- Buffalograss Bouteloua dactyloides · 9 states
- Butterflyweed Asclepias tuberosa · 37 states
- Chokecherry Prunus virginiana · 35 states
- Colorado blue columbine Aquilegia coerulea · 6 states
- Common elderberry Sambucus nigra ssp. canadensis · 16 states
- Common ninebark Physocarpus opulifolius · 22 states
- Common yarrow Achillea millefolium · 31 states
- Creeping Oregon grape Mahonia repens · 11 states
- Fireweed Chamerion angustifolium · 28 states
- Green ash Fraxinus pennsylvanica · 23 states
- Highbush cranberry Viburnum opulus var. americanum · 8 states
- Indian blanket Gaillardia pulchella · 18 states
- Indigo bush Amorpha fruticosa · 16 states
- Little bluestem Schizachyrium scoparium · 23 states
- Mexican hat Ratibida columnifera · 17 states
- Pearly everlasting Anaphalis margaritacea · 18 states
- Purple prairie clover Dalea purpurea · 5 states
- Quaking aspen Populus tremuloides · 24 states
- Red baneberry Actaea rubra · 22 states
- Red-osier dogwood Cornus sericea · 22 states
- Rocky Mountain bee plant Peritoma serrulata · 22 states
- Rocky Mountain penstemon Penstemon strictus · 4 states
- Scarlet bugler Penstemon barbatus · 2 states
- Shrubby cinquefoil Dasiphora fruticosa ssp. floribunda · 15 states
- Sideoats grama Bouteloua curtipendula · 25 states
- Smooth sumac Rhus glabra · 34 states
- Spotted beebalm Monarda punctata · 14 states
- Swamp milkweed Asclepias incarnata · 25 states