Herron, MI frost dates
Last spring frostMay 17median date
First fall frostOct 1median date
Growing season137 daysfrost-free
Hardiness zone5aZone 5a
How Herron compares
- In 8 years out of 10, the last spring frost in Herron falls between May 1 and May 31, a 30-day window. The first fall frost falls between September 18 and October 16.
- The median last frost is 12 days later than the Michigan median of May 5.
- Its 137-day growing season is longer than 18% of the 878 Michigan places with a regular frost season (state median 162 days).
- The last frost is 14 days later than the zone 5a median of May 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5a chart.
- The weather station records an average of 169 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 1 |
| 50% (median) | May 17 |
| 10% (safe for tender plants) | May 31 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 18 |
| 50% (median) | October 1 |
| 90% (late) | October 16 |
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 Herron, MI
Herron, MI frost dates — last frost May 17, first frost Oct 1, zone 5a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 22 to Mar 8Transplant outside: Apr 19 to May 3
Start indoors: Mar 8 to Mar 22Transplant outside: May 31 to Jun 14
Start indoors: Mar 8 to Mar 22Transplant outside: May 31 to Jun 14
Start indoors: Mar 22 to Apr 5Transplant outside: May 24 to Jun 7
Start indoors: Mar 22 to Apr 5Transplant outside: Apr 26 to May 10Sow outdoors: Apr 19 to May 24Plant for fall: Aug 6 to Sep 3
Start indoors: Mar 22 to Apr 5Transplant outside: Apr 19 to May 3Sow outdoors: Apr 19 to May 3Plant for fall: Jul 23 to Aug 13
Start indoors: Mar 22 to Apr 5Transplant outside: May 3 to May 17Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 22 to Apr 5Transplant outside: Apr 26 to May 10Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 22 to Apr 5Transplant outside: May 3 to May 17Plant for fall: Jun 25 to Jul 16
Start indoors: Apr 5 to Apr 19Transplant outside: Jun 7 to Jun 21Sow outdoors: Jun 7 to Jun 21
Start indoors: Apr 5 to Apr 19Transplant outside: May 24 to Jun 7
Sow outdoors: Apr 5 to Apr 26Plant for fall: Jul 9 to Jul 30
Sow outdoors: Apr 5 to Apr 26Plant for fall: Aug 6 to Aug 27
Sow outdoors: Apr 12 to May 24Plant for fall: Aug 20 to Sep 10
Start indoors: Apr 19 to Apr 26Transplant outside: May 31 to Jun 7Sow outdoors: May 24 to Jun 7Plant for fall: Jul 16 to Jul 30
Start indoors: Apr 19 to Apr 26Sow outdoors: May 24 to Jun 7Plant for fall: Jul 23 to Aug 6
Start indoors: Apr 19 to Apr 26Sow outdoors: May 24 to Jun 7
Start indoors: Apr 19 to Apr 26Transplant outside: May 31 to Jun 14
Sow outdoors: Apr 26 to May 24Plant for fall: Jul 9 to Jul 23
Sow outdoors: Apr 26 to May 24Plant for fall: Jul 23 to Aug 6
Sow outdoors: Apr 26 to May 17
Sow outdoors: May 3 to May 31Plant for fall: Jul 23 to Aug 6
Sow outdoors: May 3 to May 24Plant for fall: Aug 6 to Aug 27
Sow outdoors: May 24 to Jun 14Plant for fall: Jul 16 to Jul 30
Sow outdoors: May 24 to Jun 7
Transplant outside: May 31 to Jun 21
Plant for fall: Sep 17 to Oct 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Herron, MI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 22 – Mar 8 | Apr 19 – May 3 | — | — |
| Peppers | Mar 8 – Mar 22 | May 31 – Jun 14 | — | — |
| Eggplant | Mar 8 – Mar 22 | May 31 – Jun 14 | — | — |
| Tomatoes | Mar 22 – Apr 5 | May 24 – Jun 7 | — | — |
| Lettuce | Mar 22 – Apr 5 | Apr 26 – May 10 | Apr 19 – May 24 | Aug 6 – Sep 3 |
| Kale | Mar 22 – Apr 5 | Apr 19 – May 3 | Apr 19 – May 3 | Jul 23 – Aug 13 |
| Broccoli | Mar 22 – Apr 5 | May 3 – May 17 | — | Jun 25 – Jul 16 |
| Cabbage | Mar 22 – Apr 5 | Apr 26 – May 10 | — | Jun 25 – Jul 16 |
| Cauliflower | Mar 22 – Apr 5 | May 3 – May 17 | — | Jun 25 – Jul 16 |
| Okra | Apr 5 – Apr 19 | Jun 7 – Jun 21 | Jun 7 – Jun 21 | — |
| Basil | Apr 5 – Apr 19 | May 24 – Jun 7 | — | — |
| Peas | — | — | Apr 5 – Apr 26 | Jul 9 – Jul 30 |
| Spinach | — | — | Apr 5 – Apr 26 | Aug 6 – Aug 27 |
| Radishes | — | — | Apr 12 – May 24 | Aug 20 – Sep 10 |
| Cucumbers | Apr 19 – Apr 26 | May 31 – Jun 7 | May 24 – Jun 7 | Jul 16 – Jul 30 |
| Zucchini & Summer Squash | Apr 19 – Apr 26 | — | May 24 – Jun 7 | Jul 23 – Aug 6 |
| Winter Squash & Pumpkins | Apr 19 – Apr 26 | — | May 24 – Jun 7 | — |
| Melons & Watermelon | Apr 19 – Apr 26 | May 31 – Jun 14 | — | — |
| Carrots | — | — | Apr 26 – May 24 | Jul 9 – Jul 23 |
| Beets | — | — | Apr 26 – May 24 | Jul 23 – Aug 6 |
| Potatoes | — | — | Apr 26 – May 17 | — |
| Swiss Chard | — | — | May 3 – May 31 | Jul 23 – Aug 6 |
| Cilantro | — | — | May 3 – May 24 | Aug 6 – Aug 27 |
| Green Beans | — | — | May 24 – Jun 14 | Jul 16 – Jul 30 |
| Sweet Corn | — | — | May 24 – Jun 7 | — |
| Sweet Potatoes | — | May 31 – Jun 21 | — | — |
| Garlic | — | — | — | Sep 17 – Oct 22 |
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 Alpena Co Rgnl Ap, MI weather station, 10 km away (elevation 686 ft (209 m)).
Frost dates near Herron
- Lachine May 17 · Oct 1
- Hubbard Lake May 17 · Oct 1
- Alpena May 5 · Oct 17
- Ossineke May 5 · Oct 17
- Posen May 13 · Oct 3
- Hillman May 22 · Sep 27
- Spruce May 8 · Oct 16
- Black River May 8 · Oct 16
- Presque Isle May 13 · Oct 3
- Curran May 19 · Sep 29
Frequently asked questions
When is the last frost in Herron, MI?
The median last spring frost in Herron, MI is May 17. There is still about a 10% chance of frost after May 31, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Herron, MI?
The median first fall frost is October 1, with about a 10% chance of frost before September 18.
How long is the growing season in Herron, MI?
About 137 days between the median last spring frost and first fall frost.
What planting zone is Herron, MI?
Herron, MI is in USDA hardiness zone 5a.