Quick answer: 48 native Idaho plants have a recorded bloom range that includes May.
48 species
- Alderleaf mountain mahogany Cercocarpus montanus · 15 states
- American plum Prunus americana · 37 states
- Antelope bitterbrush Purshia tridentata · 12 states
- Arrowleaf balsamroot Balsamorhiza sagittata · 12 states
- Banana yucca Yucca baccata · 8 states
- Bearberry Arctostaphylos uva-ursi · 34 states
- Bluebunch wheatgrass Pseudoroegneria spicata · 16 states
- Broadleaf cattail Typha latifolia · 39 states
- Canada wild rye Elymus canadensis · 37 states
- Chokecherry Prunus virginiana · 44 states
- Common yarrow Achillea millefolium · 47 states
- Creeping Oregon grape Mahonia repens · 15 states
- Creeping juniper Juniperus horizontalis · 12 states
- Crevice alumroot Heuchera micrantha · 4 states
- Douglas fir Pseudotsuga menziesii · 12 states
- Globe gilia Gilia capitata · 5 states
- Gray alder Alnus incana · 26 states
- Green ash Fraxinus pennsylvanica · 43 states
- Idaho fescue Festuca idahoensis · 12 states
- Indian ricegrass Achnatherum hymenoides · 17 states
- Lewis flax (blue flax) Linum lewisii · 17 states
- Lewis' mock orange Philadelphus lewisii · 5 states
- Mule's ears Wyethia amplexicaulis · 8 states
- Munro's globemallow Sphaeralcea munroana · 9 states
- Oceanspray Holodiscus discolor · 9 states
- Ponderosa pine Pinus ponderosa · 16 states
- Prairie Junegrass Koeleria macrantha · 29 states
- Purple sage (desert sage) Salvia dorrii · 7 states
- Quaking aspen Populus tremuloides · 39 states
- Red baneberry Actaea rubra · 29 states
- Red-flowering currant Ribes sanguineum · 4 states
- Red-osier dogwood Cornus sericea · 36 states
- Rocky Mountain bee plant Peritoma serrulata · 26 states
- Rocky Mountain iris Iris missouriensis · 11 states
- Royal penstemon Penstemon speciosus · 6 states
- Saskatoon serviceberry Amelanchier alnifolia · 14 states
- Scarlet globemallow Sphaeralcea coccinea · 12 states
- Seep monkeyflower Erythranthe guttata · 15 states
- Showy milkweed Asclepias speciosa · 17 states
- Silver buffaloberry Shepherdia argentea · 17 states
- Smooth sumac Rhus glabra · 42 states
- Snowbrush ceanothus Ceanothus velutinus · 10 states
- Tufted evening primrose Oenothera caespitosa · 15 states
- Upland larkspur Delphinium nuttallianum · 13 states
- Wasatch penstemon Penstemon cyananthus · 4 states
- Western yarrow Achillea millefolium var. occidentalis · 18 states
- Winterfat Krascheninnikovia lanata · 12 states
- Wyoming Indian paintbrush Castilleja linariifolia · 9 states
May in an Idaho native garden
May is one of Idaho's busiest bloom months, with 48 of the state's 79 native plants flowering (the peak is June).
20 start blooming in May, including Bluebunch wheatgrass, Crevice alumroot and Idaho fescue. 6 finish in May, including Alderleaf mountain mahogany, Creeping juniper and Douglas fir, so this is the last chance to see them in flower.
44 of them grow in full or partial sun and 12 tolerate shade, so there are options for open beds and woodland edges alike. Sizes run from low plants like Arrowleaf balsamroot and Bluebunch wheatgrass to trees such as Alderleaf mountain mahogany and American plum. For wildlife, 33 support pollinators, 28 provide food or cover for birds and 8 are caterpillar host plants.
31 of the 48 have a seed or plant listing we verified as the wild species. Be careful buying Common yarrow: common listings for it are often a bred variety or a different species.
Good places to start
Verified wild-species listings that take sun and are widely native, so they are forgiving first plants.
- Chokecherry Prunus virginiana · Sun, Part Shade, Shade · blooms Apr-Jul
- Green ash Fraxinus pennsylvanica · Sun, Part Shade, Shade · blooms Apr-Jun
- Smooth sumac Rhus glabra · Sun, Part Shade, Shade · blooms May-Aug