Upson, WI frost dates
Last spring frostMay 23median date
First fall frostOct 1median date
Growing season131 daysfrost-free
Hardiness zone4aZone 4a
How Upson compares
- In 8 years out of 10, the last spring frost in Upson falls between May 4 and June 5, a 32-day window. The first fall frost falls between September 18 and October 16.
- The median last frost is 18 days later than the Wisconsin median of May 5.
- Its 131-day growing season is longer than 9% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is 11 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 188 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 4 |
| 50% (median) | May 23 |
| 10% (safe for tender plants) | June 5 |
| 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 Upson, WI
Upson, WI frost dates — last frost May 23, first frost Oct 1, zone 4a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Feb 28 to Mar 14Transplant outside: Apr 25 to May 9
Start indoors: Mar 14 to Mar 28Transplant outside: Jun 6 to Jun 20
Start indoors: Mar 14 to Mar 28Transplant outside: Jun 6 to Jun 20
Start indoors: Mar 28 to Apr 11Transplant outside: May 30 to Jun 13
Start indoors: Mar 28 to Apr 11Transplant outside: May 2 to May 16Sow outdoors: Apr 25 to May 30Plant for fall: Aug 6 to Sep 3
Start indoors: Mar 28 to Apr 11Transplant outside: Apr 25 to May 9Sow outdoors: Apr 25 to May 9Plant for fall: Jul 23 to Aug 13
Start indoors: Mar 28 to Apr 11Transplant outside: May 9 to May 23Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 28 to Apr 11Transplant outside: May 2 to May 16Plant for fall: Jun 25 to Jul 16
Start indoors: Mar 28 to Apr 11Transplant outside: May 9 to May 23Plant for fall: Jun 25 to Jul 16
Start indoors: Apr 11 to Apr 25Transplant outside: Jun 13 to Jun 27Sow outdoors: Jun 13 to Jun 27
Start indoors: Apr 11 to Apr 25Transplant outside: May 30 to Jun 13
Sow outdoors: Apr 11 to May 2Plant for fall: Jul 9 to Jul 30
Sow outdoors: Apr 11 to May 2Plant for fall: Aug 6 to Aug 27
Sow outdoors: Apr 18 to May 30Plant for fall: Aug 20 to Sep 10
Start indoors: Apr 25 to May 2Transplant outside: Jun 6 to Jun 13Sow outdoors: May 30 to Jun 13Plant for fall: Jul 16 to Jul 30
Start indoors: Apr 25 to May 2Sow outdoors: May 30 to Jun 13Plant for fall: Jul 23 to Aug 6
Start indoors: Apr 25 to May 2Sow outdoors: May 30 to Jun 13
Start indoors: Apr 25 to May 2Transplant outside: Jun 6 to Jun 20
Sow outdoors: May 2 to May 30Plant for fall: Jul 9 to Jul 23
Sow outdoors: May 2 to May 30Plant for fall: Jul 23 to Aug 6
Sow outdoors: May 2 to May 23
Sow outdoors: May 9 to Jun 6Plant for fall: Jul 23 to Aug 6
Sow outdoors: May 9 to May 30Plant for fall: Aug 6 to Aug 27
Sow outdoors: May 30 to Jun 20Plant for fall: Jul 16 to Jul 30
Sow outdoors: May 30 to Jun 13
Transplant outside: Jun 6 to Jun 27
Plant for fall: Sep 17 to Oct 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Upson, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 28 – Mar 14 | Apr 25 – May 9 | — | — |
| Peppers | Mar 14 – Mar 28 | Jun 6 – Jun 20 | — | — |
| Eggplant | Mar 14 – Mar 28 | Jun 6 – Jun 20 | — | — |
| Tomatoes | Mar 28 – Apr 11 | May 30 – Jun 13 | — | — |
| Lettuce | Mar 28 – Apr 11 | May 2 – May 16 | Apr 25 – May 30 | Aug 6 – Sep 3 |
| Kale | Mar 28 – Apr 11 | Apr 25 – May 9 | Apr 25 – May 9 | Jul 23 – Aug 13 |
| Broccoli | Mar 28 – Apr 11 | May 9 – May 23 | — | Jun 25 – Jul 16 |
| Cabbage | Mar 28 – Apr 11 | May 2 – May 16 | — | Jun 25 – Jul 16 |
| Cauliflower | Mar 28 – Apr 11 | May 9 – May 23 | — | Jun 25 – Jul 16 |
| Okra | Apr 11 – Apr 25 | Jun 13 – Jun 27 | Jun 13 – Jun 27 | — |
| Basil | Apr 11 – Apr 25 | May 30 – Jun 13 | — | — |
| Peas | — | — | Apr 11 – May 2 | Jul 9 – Jul 30 |
| Spinach | — | — | Apr 11 – May 2 | Aug 6 – Aug 27 |
| Radishes | — | — | Apr 18 – May 30 | Aug 20 – Sep 10 |
| Cucumbers | Apr 25 – May 2 | Jun 6 – Jun 13 | May 30 – Jun 13 | Jul 16 – Jul 30 |
| Zucchini & Summer Squash | Apr 25 – May 2 | — | May 30 – Jun 13 | Jul 23 – Aug 6 |
| Winter Squash & Pumpkins | Apr 25 – May 2 | — | May 30 – Jun 13 | — |
| Melons & Watermelon | Apr 25 – May 2 | Jun 6 – Jun 20 | — | — |
| Carrots | — | — | May 2 – May 30 | Jul 9 – Jul 23 |
| Beets | — | — | May 2 – May 30 | Jul 23 – Aug 6 |
| Potatoes | — | — | May 2 – May 23 | — |
| Swiss Chard | — | — | May 9 – Jun 6 | Jul 23 – Aug 6 |
| Cilantro | — | — | May 9 – May 30 | Aug 6 – Aug 27 |
| Green Beans | — | — | May 30 – Jun 20 | Jul 16 – Jul 30 |
| Sweet Corn | — | — | May 30 – Jun 13 | — |
| Sweet Potatoes | — | Jun 6 – Jun 27 | — | — |
| 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 Saxon 1wsw, WI weather station, 12 km away (elevation 1,165 ft (355 m)).
Frost dates near Upson
- Iron Belt May 24 · Sep 28
- Montreal May 24 · Sep 28
- Saxon May 23 · Oct 1
- Gile May 24 · Sep 28
- Hurley May 24 · Sep 28
- Mellen May 26 · Sep 27
- High Bridge May 26 · Sep 27
- Odanah May 23 · Oct 1
- Glidden May 22 · Sep 24
- Ashland May 20 · Oct 2
Frequently asked questions
When is the last frost in Upson, WI?
The median last spring frost in Upson, WI is May 23. There is still about a 10% chance of frost after June 5, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Upson, WI?
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 Upson, WI?
About 131 days between the median last spring frost and first fall frost.
What planting zone is Upson, WI?
Upson, WI is in USDA hardiness zone 4a.