Whitewater, WI frost dates
How Whitewater compares
- In 8 years out of 10, the last spring frost in Whitewater falls between April 18 and May 20, a 32-day window. The first fall frost falls between September 25 and October 24.
- The median last frost is 3 days earlier than the Wisconsin median of May 5.
- Its 160-day growing season is longer than 63% of the 749 Wisconsin places with a regular frost season (state median 155 days).
- The last frost is typical for zone 5b, where the median is May 1.
- The weather station records an average of 152 nights a year at or below 32°F.
- Compared with Janesville, WI, 29 km away, the last frost here is 6 days later than there and the growing season is 12 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 18 |
| 50% (median) | May 2 |
| 10% (safe for tender plants) | May 20 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 25 |
| 50% (median) | October 9 |
| 90% (late) | October 24 |
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 Whitewater, WI
Whitewater, WI frost dates — last frost May 2, first frost Oct 9, zone 5b. whenisthelastfrost.com
When to plant vegetables in Whitewater, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 7 – Feb 21 | Apr 4 – Apr 18 | — | — |
| Peppers | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Eggplant | Feb 21 – Mar 7 | May 16 – May 30 | — | — |
| Tomatoes | Mar 7 – Mar 21 | May 9 – May 23 | — | — |
| Lettuce | Mar 7 – Mar 21 | Apr 11 – Apr 25 | Apr 4 – May 9 | Aug 14 – Sep 11 |
| Kale | Mar 7 – Mar 21 | Apr 4 – Apr 18 | Apr 4 – Apr 18 | Jul 31 – Aug 21 |
| Broccoli | Mar 7 – Mar 21 | Apr 18 – May 2 | — | Jul 3 – Jul 24 |
| Cabbage | Mar 7 – Mar 21 | Apr 11 – Apr 25 | — | Jul 3 – Jul 24 |
| Cauliflower | Mar 7 – Mar 21 | Apr 18 – May 2 | — | Jul 3 – Jul 24 |
| Okra | Mar 21 – Apr 4 | May 23 – Jun 6 | May 23 – Jun 6 | — |
| Basil | Mar 21 – Apr 4 | May 9 – May 23 | — | — |
| Peas | — | — | Mar 21 – Apr 11 | Jul 17 – Aug 7 |
| Spinach | — | — | Mar 21 – Apr 11 | Aug 14 – Sep 4 |
| Radishes | — | — | Mar 28 – May 9 | Aug 28 – Sep 18 |
| Cucumbers | Apr 4 – Apr 11 | May 16 – May 23 | May 9 – May 23 | Jul 24 – Aug 7 |
| Zucchini & Summer Squash | Apr 4 – Apr 11 | — | May 9 – May 23 | Jul 31 – Aug 14 |
| Winter Squash & Pumpkins | Apr 4 – Apr 11 | — | May 9 – May 23 | — |
| Melons & Watermelon | Apr 4 – Apr 11 | May 16 – May 30 | — | — |
| Carrots | — | — | Apr 11 – May 9 | Jul 17 – Jul 31 |
| Beets | — | — | Apr 11 – May 9 | Jul 31 – Aug 14 |
| Potatoes | — | — | Apr 11 – May 2 | — |
| Swiss Chard | — | — | Apr 18 – May 16 | Jul 31 – Aug 14 |
| Cilantro | — | — | Apr 18 – May 9 | Aug 14 – Sep 4 |
| Green Beans | — | — | May 9 – May 30 | Jul 24 – Aug 7 |
| Sweet Corn | — | — | May 9 – May 23 | — |
| Sweet Potatoes | — | May 16 – Jun 6 | — | — |
| Garlic | — | — | — | Sep 25 – Oct 30 |
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 Whitewater, WI weather station, 3 km away (elevation 876 ft (267 m)).
Frost dates near Whitewater
- Fort Atkinson Apr 28 · Oct 13
- Palmyra May 3 · Oct 9
- Milton Apr 28 · Oct 13
- Avalon Apr 30 · Oct 10
- Jefferson Apr 25 · Oct 18
- Helenville Apr 25 · Oct 18
- Elkhorn Apr 28 · Oct 14
- Sullivan May 3 · Oct 9
- Eagle May 3 · Oct 9
- Delavan Apr 28 · Oct 14
Frequently asked questions
When is the last frost in Whitewater, WI?
The median last spring frost in Whitewater, WI is May 2. There is still about a 10% chance of frost after May 20, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Whitewater, WI?
The median first fall frost is October 9, with about a 10% chance of frost before September 25.
How long is the growing season in Whitewater, WI?
About 160 days between the median last spring frost and first fall frost.
What planting zone is Whitewater, WI?
Whitewater, WI is in USDA hardiness zone 5b.