Foxboro, WI frost dates
Last spring frostMay 18median date
First fall frostOct 3median date
Growing season138 daysfrost-free
Hardiness zone4aZone 4a
How Foxboro compares
- In 8 years out of 10, the last spring frost in Foxboro falls between May 4 and June 3, a 30-day window. The first fall frost falls between September 20 and October 16.
- The median last frost is 13 days later than the Wisconsin median of May 5.
- Its 138-day growing season is longer than 14% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is 6 days later than the zone 4a median of May 12. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4a chart.
- The weather station records an average of 180 nights a year at or below 32°F.
- Compared with Duluth, MN, 33 km away, the last frost here is 4 days later than there and the growing season is 13 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 4 |
| 50% (median) | May 18 |
| 10% (safe for tender plants) | June 3 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 20 |
| 50% (median) | October 3 |
| 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 Foxboro, WI
Foxboro, WI frost dates — last frost May 18, first frost Oct 3, zone 4a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 23 to Mar 9Transplant outside: Apr 20 to May 4
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 23 to Apr 6Transplant outside: May 25 to Jun 8
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Sow outdoors: Apr 20 to May 25Plant for fall: Aug 8 to Sep 5
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 20 to May 4Sow outdoors: Apr 20 to May 4Plant for fall: Jul 25 to Aug 15
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 27 to Jul 18
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Plant for fall: Jun 27 to Jul 18
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 27 to Jul 18
Start indoors: Apr 6 to Apr 20Transplant outside: Jun 8 to Jun 22Sow outdoors: Jun 8 to Jun 22
Start indoors: Apr 6 to Apr 20Transplant outside: May 25 to Jun 8
Sow outdoors: Apr 6 to Apr 27Plant for fall: Jul 11 to Aug 1
Sow outdoors: Apr 6 to Apr 27Plant for fall: Aug 8 to Aug 29
Sow outdoors: Apr 13 to May 25Plant for fall: Aug 22 to Sep 12
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 8Sow outdoors: May 25 to Jun 8Plant for fall: Jul 18 to Aug 1
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8Plant for fall: Jul 25 to Aug 8
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 15
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 11 to Jul 25
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 25 to Aug 8
Sow outdoors: Apr 27 to May 18
Sow outdoors: May 4 to Jun 1Plant for fall: Jul 25 to Aug 8
Sow outdoors: May 4 to May 25Plant for fall: Aug 8 to Aug 29
Sow outdoors: May 25 to Jun 15Plant for fall: Jul 18 to Aug 1
Sow outdoors: May 25 to Jun 8
Transplant outside: Jun 1 to Jun 22
Plant for fall: Sep 19 to Oct 24
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Foxboro, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 23 – Mar 9 | Apr 20 – May 4 | — | — |
| Peppers | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Eggplant | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Tomatoes | Mar 23 – Apr 6 | May 25 – Jun 8 | — | — |
| Lettuce | Mar 23 – Apr 6 | Apr 27 – May 11 | Apr 20 – May 25 | Aug 8 – Sep 5 |
| Kale | Mar 23 – Apr 6 | Apr 20 – May 4 | Apr 20 – May 4 | Jul 25 – Aug 15 |
| Broccoli | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 27 – Jul 18 |
| Cabbage | Mar 23 – Apr 6 | Apr 27 – May 11 | — | Jun 27 – Jul 18 |
| Cauliflower | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 27 – Jul 18 |
| Okra | Apr 6 – Apr 20 | Jun 8 – Jun 22 | Jun 8 – Jun 22 | — |
| Basil | Apr 6 – Apr 20 | May 25 – Jun 8 | — | — |
| Peas | — | — | Apr 6 – Apr 27 | Jul 11 – Aug 1 |
| Spinach | — | — | Apr 6 – Apr 27 | Aug 8 – Aug 29 |
| Radishes | — | — | Apr 13 – May 25 | Aug 22 – Sep 12 |
| Cucumbers | Apr 20 – Apr 27 | Jun 1 – Jun 8 | May 25 – Jun 8 | Jul 18 – Aug 1 |
| Zucchini & Summer Squash | Apr 20 – Apr 27 | — | May 25 – Jun 8 | Jul 25 – Aug 8 |
| Winter Squash & Pumpkins | Apr 20 – Apr 27 | — | May 25 – Jun 8 | — |
| Melons & Watermelon | Apr 20 – Apr 27 | Jun 1 – Jun 15 | — | — |
| Carrots | — | — | Apr 27 – May 25 | Jul 11 – Jul 25 |
| Beets | — | — | Apr 27 – May 25 | Jul 25 – Aug 8 |
| Potatoes | — | — | Apr 27 – May 18 | — |
| Swiss Chard | — | — | May 4 – Jun 1 | Jul 25 – Aug 8 |
| Cilantro | — | — | May 4 – May 25 | Aug 8 – Aug 29 |
| Green Beans | — | — | May 25 – Jun 15 | Jul 18 – Aug 1 |
| Sweet Corn | — | — | May 25 – Jun 8 | — |
| Sweet Potatoes | — | Jun 1 – Jun 22 | — | — |
| Garlic | — | — | — | Sep 19 – Oct 24 |
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 Pattison Ranger Staion, WI weather station, 6 km away (elevation 1,099 ft (335 m)).
Frost dates near Foxboro
- South Range May 18 · Oct 3
- Hawthorne May 12 · Oct 2
- Superior May 6 · Oct 9
- Poplar May 24 · Sep 26
- Solon Springs May 12 · Oct 2
- Lake Nebagamon May 24 · Sep 26
- Maple May 24 · Sep 26
- Gordon May 22 · Sep 26
- Wascott May 22 · Sep 26
- Brule May 24 · Sep 26
Frequently asked questions
When is the last frost in Foxboro, WI?
The median last spring frost in Foxboro, WI is May 18. 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 Foxboro, WI?
The median first fall frost is October 3, with about a 10% chance of frost before September 20.
How long is the growing season in Foxboro, WI?
About 138 days between the median last spring frost and first fall frost.
What planting zone is Foxboro, WI?
Foxboro, WI is in USDA hardiness zone 4a.