Spooner, WI frost dates
How Spooner compares
- In 8 years out of 10, the last spring frost in Spooner falls between April 30 and May 29, a 29-day window. The first fall frost falls between September 14 and October 11.
- The median last frost is 9 days later than the Wisconsin median of May 5.
- Its 137-day growing season is longer than 13% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is typical for zone 4a, where the median is May 12.
- The weather station records an average of 171 nights a year at or below 32°F.
- Compared with Duluth, MN, 105 km away, the last frost here is the same as there and the growing season is 14 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 30 |
| 50% (median) | May 14 |
| 10% (safe for tender plants) | May 29 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 14 |
| 50% (median) | September 28 |
| 90% (late) | October 11 |
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 Spooner, WI
Spooner, WI frost dates — last frost May 14, first frost Sep 28, zone 4a. whenisthelastfrost.com
When to plant vegetables in Spooner, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 19 – Mar 5 | Apr 16 – Apr 30 | — | — |
| Peppers | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Eggplant | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Tomatoes | Mar 19 – Apr 2 | May 21 – Jun 4 | — | — |
| Lettuce | Mar 19 – Apr 2 | Apr 23 – May 7 | Apr 16 – May 21 | Aug 3 – Aug 31 |
| Kale | Mar 19 – Apr 2 | Apr 16 – Apr 30 | Apr 16 – Apr 30 | Jul 20 – Aug 10 |
| Broccoli | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 22 – Jul 13 |
| Cabbage | Mar 19 – Apr 2 | Apr 23 – May 7 | — | Jun 22 – Jul 13 |
| Cauliflower | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 22 – Jul 13 |
| Okra | Apr 2 – Apr 16 | Jun 4 – Jun 18 | Jun 4 – Jun 18 | — |
| Basil | Apr 2 – Apr 16 | May 21 – Jun 4 | — | — |
| Peas | — | — | Apr 2 – Apr 23 | Jul 6 – Jul 27 |
| Spinach | — | — | Apr 2 – Apr 23 | Aug 3 – Aug 24 |
| Radishes | — | — | Apr 9 – May 21 | Aug 17 – Sep 7 |
| Cucumbers | Apr 16 – Apr 23 | May 28 – Jun 4 | May 21 – Jun 4 | Jul 13 – Jul 27 |
| Zucchini & Summer Squash | Apr 16 – Apr 23 | — | May 21 – Jun 4 | Jul 20 – Aug 3 |
| Winter Squash & Pumpkins | Apr 16 – Apr 23 | — | May 21 – Jun 4 | — |
| Melons & Watermelon | Apr 16 – Apr 23 | May 28 – Jun 11 | — | — |
| Carrots | — | — | Apr 23 – May 21 | Jul 6 – Jul 20 |
| Beets | — | — | Apr 23 – May 21 | Jul 20 – Aug 3 |
| Potatoes | — | — | Apr 23 – May 14 | — |
| Swiss Chard | — | — | Apr 30 – May 28 | Jul 20 – Aug 3 |
| Cilantro | — | — | Apr 30 – May 21 | Aug 3 – Aug 24 |
| Green Beans | — | — | May 21 – Jun 11 | Jul 13 – Jul 27 |
| Sweet Corn | — | — | May 21 – Jun 4 | — |
| Sweet Potatoes | — | May 28 – Jun 18 | — | — |
| 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 Spooner Ag Res Stn, WI weather station, 4 km away (elevation 1,099 ft (335 m)).
Frost dates near Spooner
- Shell Lake May 14 · Sep 28
- Trego May 10 · Oct 4
- Hertel May 14 · Sep 28
- Sarona May 14 · Sep 28
- Springbrook May 22 · Sep 23
- Barronett May 5 · Oct 4
- Minong May 10 · Oct 4
- Haugen May 5 · Oct 4
- Stone Lake frost any month
- Webster May 11 · Sep 30
Frequently asked questions
When is the last frost in Spooner, WI?
The median last spring frost in Spooner, WI is May 14. There is still about a 10% chance of frost after May 29, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Spooner, WI?
The median first fall frost is September 28, with about a 10% chance of frost before September 14.
How long is the growing season in Spooner, WI?
About 137 days between the median last spring frost and first fall frost.
What planting zone is Spooner, WI?
Spooner, WI is in USDA hardiness zone 4a.