Trevor, WI frost dates
How Trevor compares
- In 8 years out of 10, the last spring frost in Trevor falls between April 9 and May 9, a 30-day window. The first fall frost falls between October 6 and November 3.
- The median last frost is 12 days earlier than the Wisconsin median of May 5.
- Its 181-day growing season is longer than 96% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is 8 days earlier than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 133 nights a year at or below 32°F.
- Compared with Kenosha, WI, 25 km away, the last frost here is 4 days later than there and the growing season is 9 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 9 |
| 50% (median) | April 23 |
| 10% (safe for tender plants) | May 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 6 |
| 50% (median) | October 21 |
| 90% (late) | November 3 |
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 Trevor, WI
Trevor, WI frost dates — last frost Apr 23, first frost Oct 21, zone 5b. whenisthelastfrost.com
When to plant vegetables in Trevor, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 29 – Feb 12 | Mar 26 – Apr 9 | — | — |
| Peppers | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Eggplant | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Tomatoes | Feb 26 – Mar 12 | Apr 30 – May 14 | — | — |
| Lettuce | Feb 26 – Mar 12 | Apr 2 – Apr 16 | Mar 26 – Apr 30 | Aug 26 – Sep 23 |
| Kale | Feb 26 – Mar 12 | Mar 26 – Apr 9 | Mar 26 – Apr 9 | Aug 12 – Sep 2 |
| Broccoli | Feb 26 – Mar 12 | Apr 9 – Apr 23 | — | Jul 15 – Aug 5 |
| Cabbage | Feb 26 – Mar 12 | Apr 2 – Apr 16 | — | Jul 15 – Aug 5 |
| Cauliflower | Feb 26 – Mar 12 | Apr 9 – Apr 23 | — | Jul 15 – Aug 5 |
| Okra | Mar 12 – Mar 26 | May 14 – May 28 | May 14 – May 28 | — |
| Basil | Mar 12 – Mar 26 | Apr 30 – May 14 | — | — |
| Peas | — | — | Mar 12 – Apr 2 | Jul 29 – Aug 19 |
| Spinach | — | — | Mar 12 – Apr 2 | Aug 26 – Sep 16 |
| Radishes | — | — | Mar 19 – Apr 30 | Sep 9 – Sep 30 |
| Cucumbers | Mar 26 – Apr 2 | May 7 – May 14 | Apr 30 – May 14 | Aug 5 – Aug 19 |
| Zucchini & Summer Squash | Mar 26 – Apr 2 | — | Apr 30 – May 14 | Aug 12 – Aug 26 |
| Winter Squash & Pumpkins | Mar 26 – Apr 2 | — | Apr 30 – May 14 | — |
| Melons & Watermelon | Mar 26 – Apr 2 | May 7 – May 21 | — | — |
| Carrots | — | — | Apr 2 – Apr 30 | Jul 29 – Aug 12 |
| Beets | — | — | Apr 2 – Apr 30 | Aug 12 – Aug 26 |
| Potatoes | — | — | Apr 2 – Apr 23 | — |
| Swiss Chard | — | — | Apr 9 – May 7 | Aug 12 – Aug 26 |
| Cilantro | — | — | Apr 9 – Apr 30 | Aug 26 – Sep 16 |
| Green Beans | — | — | Apr 30 – May 21 | Aug 5 – Aug 19 |
| Sweet Corn | — | — | Apr 30 – May 14 | — |
| Sweet Potatoes | — | May 7 – May 28 | — | — |
| Garlic | — | — | — | Oct 7 – Nov 11 |
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 Antioch, IL weather station, 5 km away (elevation 751 ft (229 m)).
Frost dates near Trevor
- Camp Lake Apr 30 · Oct 15
- Wilmot Apr 23 · Oct 21
- Silver Lake Apr 30 · Oct 15
- Benet Lake Apr 23 · Oct 21
- Salem Apr 30 · Oct 15
- Bristol Apr 30 · Oct 15
- Bassett Apr 30 · Oct 13
- Twin Lakes Apr 30 · Oct 13
- New Munster May 5 · Oct 9
- Woodworth Apr 28 · Oct 19
Frequently asked questions
When is the last frost in Trevor, WI?
The median last spring frost in Trevor, WI is April 23. There is still about a 10% chance of frost after May 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Trevor, WI?
The median first fall frost is October 21, with about a 10% chance of frost before October 6.
How long is the growing season in Trevor, WI?
About 181 days between the median last spring frost and first fall frost.
What planting zone is Trevor, WI?
Trevor, WI is in USDA hardiness zone 5b.