All states › Zone 5a
USDA Hardiness Zone 5a
Zone 5a on the 2023 USDA Plant Hardiness Zone Map means an average annual extreme minimum temperature of -20°F to -15°F, averaged over 1991 to 2020. The zone is about the coldest winter night, not frost dates or summer heat, so towns in the same zone can have different frost dates.
Towns in zone 5a
- WaterlooZone 5a, median last frost Apr 27
- BangorZone 5a, median last frost May 4
- MinneapolisZone 5a, median last frost Apr 23
- BillingsZone 5a, median last frost May 4
- BozemanZone 5a, median last frost May 26
- Sioux FallsZone 5a, median last frost May 1
- CasperZone 5a, median last frost May 10