Bessemer, MI frost dates
Last spring frostMay 19median date
First fall frostSep 28median date
Growing season132 daysfrost-free
Hardiness zone4bZone 4b
How Bessemer compares
- In 8 years out of 10, the last spring frost in Bessemer falls between May 2 and June 3, a 32-day window. The first fall frost falls between September 12 and October 10.
- The median last frost is 14 days later than the Michigan median of May 5.
- Its 132-day growing season is longer than 13% of the 878 Michigan places with a regular frost season (state median 162 days).
- The last frost is 11 days later than the zone 4b median of May 8. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4b chart.
- The weather station records an average of 203 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 2 |
| 50% (median) | May 19 |
| 10% (safe for tender plants) | June 3 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 12 |
| 50% (median) | September 28 |
| 90% (late) | October 10 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Bessemer, MI
Bessemer, MI frost dates — last frost May 19, first frost Sep 28, zone 4b. whenisthelastfrost.com
Crop
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Start indoors: Feb 24 to Mar 10Transplant outside: Apr 21 to May 5
Start indoors: Mar 10 to Mar 24Transplant outside: Jun 2 to Jun 16
Start indoors: Mar 10 to Mar 24Transplant outside: Jun 2 to Jun 16
Start indoors: Mar 24 to Apr 7Transplant outside: May 26 to Jun 9
Start indoors: Mar 24 to Apr 7Transplant outside: Apr 28 to May 12Sow outdoors: Apr 21 to May 26Plant for fall: Aug 3 to Aug 31
Start indoors: Mar 24 to Apr 7Transplant outside: Apr 21 to May 5Sow outdoors: Apr 21 to May 5Plant for fall: Jul 20 to Aug 10
Start indoors: Mar 24 to Apr 7Transplant outside: May 5 to May 19Plant for fall: Jun 22 to Jul 13
Start indoors: Mar 24 to Apr 7Transplant outside: Apr 28 to May 12Plant for fall: Jun 22 to Jul 13
Start indoors: Mar 24 to Apr 7Transplant outside: May 5 to May 19Plant for fall: Jun 22 to Jul 13
Start indoors: Apr 7 to Apr 21Transplant outside: Jun 9 to Jun 23Sow outdoors: Jun 9 to Jun 23
Start indoors: Apr 7 to Apr 21Transplant outside: May 26 to Jun 9
Sow outdoors: Apr 7 to Apr 28Plant for fall: Jul 6 to Jul 27
Sow outdoors: Apr 7 to Apr 28Plant for fall: Aug 3 to Aug 24
Sow outdoors: Apr 14 to May 26Plant for fall: Aug 17 to Sep 7
Start indoors: Apr 21 to Apr 28Transplant outside: Jun 2 to Jun 9Sow outdoors: May 26 to Jun 9Plant for fall: Jul 13 to Jul 27
Start indoors: Apr 21 to Apr 28Sow outdoors: May 26 to Jun 9Plant for fall: Jul 20 to Aug 3
Start indoors: Apr 21 to Apr 28Sow outdoors: May 26 to Jun 9
Start indoors: Apr 21 to Apr 28Transplant outside: Jun 2 to Jun 16
Sow outdoors: Apr 28 to May 26Plant for fall: Jul 6 to Jul 20
Sow outdoors: Apr 28 to May 26Plant for fall: Jul 20 to Aug 3
Sow outdoors: Apr 28 to May 19
Sow outdoors: May 5 to Jun 2Plant for fall: Jul 20 to Aug 3
Sow outdoors: May 5 to May 26Plant for fall: Aug 3 to Aug 24
Sow outdoors: May 26 to Jun 16Plant for fall: Jul 13 to Jul 27
Sow outdoors: May 26 to Jun 9
Transplant outside: Jun 2 to Jun 23
Plant for fall: Sep 14 to Oct 19
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Bessemer, MI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 24 – Mar 10 | Apr 21 – May 5 | — | — |
| Peppers | Mar 10 – Mar 24 | Jun 2 – Jun 16 | — | — |
| Eggplant | Mar 10 – Mar 24 | Jun 2 – Jun 16 | — | — |
| Tomatoes | Mar 24 – Apr 7 | May 26 – Jun 9 | — | — |
| Lettuce | Mar 24 – Apr 7 | Apr 28 – May 12 | Apr 21 – May 26 | Aug 3 – Aug 31 |
| Kale | Mar 24 – Apr 7 | Apr 21 – May 5 | Apr 21 – May 5 | Jul 20 – Aug 10 |
| Broccoli | Mar 24 – Apr 7 | May 5 – May 19 | — | Jun 22 – Jul 13 |
| Cabbage | Mar 24 – Apr 7 | Apr 28 – May 12 | — | Jun 22 – Jul 13 |
| Cauliflower | Mar 24 – Apr 7 | May 5 – May 19 | — | Jun 22 – Jul 13 |
| Okra | Apr 7 – Apr 21 | Jun 9 – Jun 23 | Jun 9 – Jun 23 | — |
| Basil | Apr 7 – Apr 21 | May 26 – Jun 9 | — | — |
| Peas | — | — | Apr 7 – Apr 28 | Jul 6 – Jul 27 |
| Spinach | — | — | Apr 7 – Apr 28 | Aug 3 – Aug 24 |
| Radishes | — | — | Apr 14 – May 26 | Aug 17 – Sep 7 |
| Cucumbers | Apr 21 – Apr 28 | Jun 2 – Jun 9 | May 26 – Jun 9 | Jul 13 – Jul 27 |
| Zucchini & Summer Squash | Apr 21 – Apr 28 | — | May 26 – Jun 9 | Jul 20 – Aug 3 |
| Winter Squash & Pumpkins | Apr 21 – Apr 28 | — | May 26 – Jun 9 | — |
| Melons & Watermelon | Apr 21 – Apr 28 | Jun 2 – Jun 16 | — | — |
| Carrots | — | — | Apr 28 – May 26 | Jul 6 – Jul 20 |
| Beets | — | — | Apr 28 – May 26 | Jul 20 – Aug 3 |
| Potatoes | — | — | Apr 28 – May 19 | — |
| Swiss Chard | — | — | May 5 – Jun 2 | Jul 20 – Aug 3 |
| Cilantro | — | — | May 5 – May 26 | Aug 3 – Aug 24 |
| Green Beans | — | — | May 26 – Jun 16 | Jul 13 – Jul 27 |
| Sweet Corn | — | — | May 26 – Jun 9 | — |
| Sweet Potatoes | — | Jun 2 – Jun 23 | — | — |
| Garlic | — | — | — | Sep 14 – Oct 19 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Ironwood #2, MI weather station, 7 km away (elevation 1,519 ft (463 m)).
Frost dates near Bessemer
- Ramsay May 19 · Sep 28
- Ironwood May 19 · Sep 28
- Wakefield May 19 · Sep 28
- Marenisco May 26 · Sep 27
- Bergland May 26 · Sep 27
- White Pine May 26 · Sep 27
- Ewen May 26 · Sep 27
- Ontonagon May 27 · Oct 1
- Bruce Crossing May 31 · Sep 19
- Watersmeet May 31 · Sep 19
Frequently asked questions
When is the last frost in Bessemer, MI?
The median last spring frost in Bessemer, MI is May 19. There is still about a 10% chance of frost after June 3, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Bessemer, MI?
The median first fall frost is September 28, with about a 10% chance of frost before September 12.
How long is the growing season in Bessemer, MI?
About 132 days between the median last spring frost and first fall frost.
What planting zone is Bessemer, MI?
Bessemer, MI is in USDA hardiness zone 4b.