Walnut, IL frost dates
How Walnut compares
- In 8 years out of 10, the last spring frost in Walnut falls between April 10 and May 9, a 29-day window. The first fall frost falls between September 30 and October 27.
- The median last frost is 7 days later than the Illinois median of Apr 17.
- Its 173-day growing season is longer than 12% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 7 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 136 nights a year at or below 32°F.
- Compared with Davenport, IA, 82 km away, the last frost here is 1 day later than there and the growing season is 2 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 10 |
| 50% (median) | April 24 |
| 10% (safe for tender plants) | May 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 30 |
| 50% (median) | October 14 |
| 90% (late) | October 27 |
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 Walnut, IL
Walnut, IL frost dates — last frost Apr 24, first frost Oct 14, zone 5b. whenisthelastfrost.com
When to plant vegetables in Walnut, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 30 – Feb 13 | Mar 27 – Apr 10 | — | — |
| Peppers | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Eggplant | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Tomatoes | Feb 27 – Mar 13 | May 1 – May 15 | — | — |
| Lettuce | Feb 27 – Mar 13 | Apr 3 – Apr 17 | Mar 27 – May 1 | Aug 19 – Sep 16 |
| Kale | Feb 27 – Mar 13 | Mar 27 – Apr 10 | Mar 27 – Apr 10 | Aug 5 – Aug 26 |
| Broccoli | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 8 – Jul 29 |
| Cabbage | Feb 27 – Mar 13 | Apr 3 – Apr 17 | — | Jul 8 – Jul 29 |
| Cauliflower | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 8 – Jul 29 |
| Okra | Mar 13 – Mar 27 | May 15 – May 29 | May 15 – May 29 | — |
| Basil | Mar 13 – Mar 27 | May 1 – May 15 | — | — |
| Peas | — | — | Mar 13 – Apr 3 | Jul 22 – Aug 12 |
| Spinach | — | — | Mar 13 – Apr 3 | Aug 19 – Sep 9 |
| Radishes | — | — | Mar 20 – May 1 | Sep 2 – Sep 23 |
| Cucumbers | Mar 27 – Apr 3 | May 8 – May 15 | May 1 – May 15 | Jul 29 – Aug 12 |
| Zucchini & Summer Squash | Mar 27 – Apr 3 | — | May 1 – May 15 | Aug 5 – Aug 19 |
| Winter Squash & Pumpkins | Mar 27 – Apr 3 | — | May 1 – May 15 | — |
| Melons & Watermelon | Mar 27 – Apr 3 | May 8 – May 22 | — | — |
| Carrots | — | — | Apr 3 – May 1 | Jul 22 – Aug 5 |
| Beets | — | — | Apr 3 – May 1 | Aug 5 – Aug 19 |
| Potatoes | — | — | Apr 3 – Apr 24 | — |
| Swiss Chard | — | — | Apr 10 – May 8 | Aug 5 – Aug 19 |
| Cilantro | — | — | Apr 10 – May 1 | Aug 19 – Sep 9 |
| Green Beans | — | — | May 1 – May 22 | Jul 29 – Aug 12 |
| Sweet Corn | — | — | May 1 – May 15 | — |
| Sweet Potatoes | — | May 8 – May 29 | — | — |
| Garlic | — | — | — | Sep 30 – Nov 4 |
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 Walnut, IL weather station, 2 km away (elevation 673 ft (205 m)).
Frost dates near Walnut
- New Bedford Apr 24 · Oct 14
- Manlius Apr 24 · Oct 14
- Ohio Apr 24 · Oct 14
- Deer Grove Apr 24 · Oct 14
- Kasbeer Apr 24 · Oct 14
- Harmon Apr 24 · Oct 14
- Wyanet Apr 22 · Oct 17
- Sheffield Apr 24 · Oct 14
- Tampico Apr 24 · Oct 14
- Dover Apr 22 · Oct 17
Frequently asked questions
When is the last frost in Walnut, IL?
The median last spring frost in Walnut, IL is April 24. 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 Walnut, IL?
The median first fall frost is October 14, with about a 10% chance of frost before September 30.
How long is the growing season in Walnut, IL?
About 173 days between the median last spring frost and first fall frost.
What planting zone is Walnut, IL?
Walnut, IL is in USDA hardiness zone 5b.