Last frost date in Janesville, Wisconsin
April 26
Average last frost in spring. In an early year (1 in 10) it's over by April 13; in a late year (1 in 10) it comes after May 11.
October 15
Average first frost in fall. 1 year in 10 it comes by October 1.
Source: NOAA U.S. Climate Normals 1991–2020, station Afton - Janesville Wwtp (USC00470045), 4.2 miles from Janesville, elevation 762 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | Apr 13 | Apr 26 | May 11 |
| First frost in fall | Oct 1 | Oct 15 | Oct 27 |
Frost-free days in an average year: 170
| Chance in a year | Average last in spring | Average first in fall | |
|---|---|---|---|
| Light frost (36°F) | Every year | May 6 | Oct 4 |
| Frost (32°F) | Every year | Apr 26 | Oct 15 |
| Hard freeze (28°F) | Every year | Apr 15 | Oct 26 |
Nights at 32°F or colder in an average year: 148
What to plant now in Janesville
- Spring planting calendar for an average last frost around April 30 Janesville: April 26
- Fall planting calendar for an average first frost around October 10 Janesville: October 15
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.
Nearby in Wisconsin
- Beloit 11 mi · last frost May 1
- Whitewater 18 mi · last frost May 2
- Fort Atkinson 19 mi · last frost Apr 28
- Stoughton 20 mi · last frost Apr 30
- Elkhorn 24 mi · last frost Apr 28