Michigan Frost Dates and Planting Zones
Across 1,158 ZIP codes we matched to a NOAA weather station, Michigan’s last spring frost (50% risk, 32°F) ranges from Jun 7 near Vanderbilt 11ene to Apr 17 near s Haven. First fall frost runs from Sep 9 near Amasa 1w to Nov 5 near s Haven. Look up your exact ZIP code on the frost date tool for a station-matched result and hardiness zone.
Frost dates by city in Michigan
The 12 weather stations covering the most MI ZIP codes, at the 50% and 10% probability levels (32°F threshold). The 10% date is later and safer to plant after; the 50% date is the typical planning date.
| Station | Last frost (50%) | Last frost (10%) | First frost (50%) | First frost (10%) |
|---|---|---|---|---|
| Pontiac Wwtp | Apr 26 | May 12 | Oct 22 | Oct 7 |
| Dearborn #2 | Apr 27 | May 11 | Oct 25 | Oct 10 |
| e Grand Rapids | May 6 | May 23 | Oct 10 | Sep 29 |
| Kalamazoo Battle ck Intl ap | Apr 28 | May 13 | Oct 18 | Oct 2 |
| Detroit City ap | Apr 21 | May 6 | Oct 31 | Oct 17 |
| Lansing Capital City ap | May 1 | May 18 | Oct 13 | Sep 29 |
| mt Clemens Ang Base | Apr 30 | May 15 | Oct 24 | Oct 7 |
| Farmington | May 1 | May 16 | Oct 17 | Oct 1 |
| Saint Johns | Apr 28 | May 12 | Oct 24 | Oct 7 |
| Kent City 2 sw | May 14 | May 31 | Sep 29 | Sep 14 |
| Detroit Willow Run ap | Apr 24 | May 11 | Oct 24 | Oct 7 |
| Flint 7w | May 3 | May 20 | Oct 13 | Sep 30 |
USDA hardiness zones in Michigan
Share of Michigan ZIP codes in each 2023 USDA Plant Hardiness Zone. 41.2% of MI ZIP codes moved to a different zone between the 2012 and 2023 maps, mostly warming as winter lows trended up.
| Zone (2023) | Share of MI ZIPs |
|---|---|
| 4a | 1.1% |
| 4b | 3.3% |
| 5a | 11.4% |
| 5b | 9.4% |
| 6a | 55.5% |
| 6b | 19.2% |
| 7a | 0.1% |
Climate is shifting
Averaged across MI stations with both normals periods, the last spring frost now lands about 2 days earlier than the 1981–2010 normal. First fall frost now lands about 5 days later, stretching or shrinking the frost-free season depending on the station.
Plan around your Michigan frost dates
Once you know your local last and first frost, these guides help you time the work around them: