Richfield, WI frost dates
How Richfield compares
- In 8 years out of 10, the last spring frost in Richfield falls between April 15 and May 15, a 30-day window. The first fall frost falls between October 1 and October 29.
- The median last frost is 5 days earlier than the Wisconsin median of May 5.
- Its 168-day growing season is longer than 83% 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 146 nights a year at or below 32°F.
- Compared with Waukesha, WI, 31 km away, the last frost here is 1 day earlier than there and the growing season is 3 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 15 |
| 50% (median) | April 30 |
| 10% (safe for tender plants) | May 15 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 1 |
| 50% (median) | October 15 |
| 90% (late) | October 29 |
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 Richfield, WI
Richfield, WI frost dates — last frost Apr 30, first frost Oct 15, zone 5b. whenisthelastfrost.com
When to plant vegetables in Richfield, WI
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 5 – Feb 19 | Apr 2 – Apr 16 | — | — |
| Peppers | Feb 19 – Mar 5 | May 14 – May 28 | — | — |
| Eggplant | Feb 19 – Mar 5 | May 14 – May 28 | — | — |
| Tomatoes | Mar 5 – Mar 19 | May 7 – May 21 | — | — |
| Lettuce | Mar 5 – Mar 19 | Apr 9 – Apr 23 | Apr 2 – May 7 | Aug 20 – Sep 17 |
| Kale | Mar 5 – Mar 19 | Apr 2 – Apr 16 | Apr 2 – Apr 16 | Aug 6 – Aug 27 |
| Broccoli | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jul 9 – Jul 30 |
| Cabbage | Mar 5 – Mar 19 | Apr 9 – Apr 23 | — | Jul 9 – Jul 30 |
| Cauliflower | Mar 5 – Mar 19 | Apr 16 – Apr 30 | — | Jul 9 – Jul 30 |
| Okra | Mar 19 – Apr 2 | May 21 – Jun 4 | May 21 – Jun 4 | — |
| Basil | Mar 19 – Apr 2 | May 7 – May 21 | — | — |
| Peas | — | — | Mar 19 – Apr 9 | Jul 23 – Aug 13 |
| Spinach | — | — | Mar 19 – Apr 9 | Aug 20 – Sep 10 |
| Radishes | — | — | Mar 26 – May 7 | Sep 3 – Sep 24 |
| Cucumbers | Apr 2 – Apr 9 | May 14 – May 21 | May 7 – May 21 | Jul 30 – Aug 13 |
| Zucchini & Summer Squash | Apr 2 – Apr 9 | — | May 7 – May 21 | Aug 6 – Aug 20 |
| Winter Squash & Pumpkins | Apr 2 – Apr 9 | — | May 7 – May 21 | — |
| Melons & Watermelon | Apr 2 – Apr 9 | May 14 – May 28 | — | — |
| Carrots | — | — | Apr 9 – May 7 | Jul 23 – Aug 6 |
| Beets | — | — | Apr 9 – May 7 | Aug 6 – Aug 20 |
| Potatoes | — | — | Apr 9 – Apr 30 | — |
| Swiss Chard | — | — | Apr 16 – May 14 | Aug 6 – Aug 20 |
| Cilantro | — | — | Apr 16 – May 7 | Aug 20 – Sep 10 |
| Green Beans | — | — | May 7 – May 28 | Jul 30 – Aug 13 |
| Sweet Corn | — | — | May 7 – May 21 | — |
| Sweet Potatoes | — | May 14 – Jun 4 | — | — |
| Garlic | — | — | — | Oct 1 – Nov 5 |
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 Jackson, WI weather station, 6 km away (elevation 902 ft (275 m)).
Frost dates near Richfield
- Hubertus Apr 30 · Oct 16
- Jackson Apr 30 · Oct 15
- Slinger May 5 · Oct 5
- Colgate Apr 30 · Oct 16
- Germantown May 6 · Oct 8
- Hartford May 8 · Oct 3
- Menomonee Falls May 6 · Oct 8
- Lannon Apr 30 · Oct 16
- Sussex Apr 30 · Oct 16
- Merton Apr 30 · Oct 16
Frequently asked questions
When is the last frost in Richfield, WI?
The median last spring frost in Richfield, WI is April 30. There is still about a 10% chance of frost after May 15, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Richfield, WI?
The median first fall frost is October 15, with about a 10% chance of frost before October 1.
How long is the growing season in Richfield, WI?
About 168 days between the median last spring frost and first fall frost.
What planting zone is Richfield, WI?
Richfield, WI is in USDA hardiness zone 5b.