Rochelle, IL frost dates
How Rochelle compares
- In 8 years out of 10, the last spring frost in Rochelle falls between April 11 and May 12, a 31-day window. The first fall frost falls between September 29 and October 25.
- The median last frost is 9 days later than the Illinois median of Apr 17.
- Its 170-day growing season is longer than 6% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 5 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 145 nights a year at or below 32°F.
- Compared with Rockford, IL, 40 km away, the last frost here is 2 days later than there and the growing season is 6 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 11 |
| 50% (median) | April 26 |
| 10% (safe for tender plants) | May 12 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 29 |
| 50% (median) | October 13 |
| 90% (late) | October 25 |
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 Rochelle, IL
Rochelle, IL frost dates — last frost Apr 26, first frost Oct 13, zone 5b. whenisthelastfrost.com
When to plant vegetables in Rochelle, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 1 – Feb 15 | Mar 29 – Apr 12 | — | — |
| Peppers | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Eggplant | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Tomatoes | Mar 1 – Mar 15 | May 3 – May 17 | — | — |
| Lettuce | Mar 1 – Mar 15 | Apr 5 – Apr 19 | Mar 29 – May 3 | Aug 18 – Sep 15 |
| Kale | Mar 1 – Mar 15 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | Aug 4 – Aug 25 |
| Broccoli | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 7 – Jul 28 |
| Cabbage | Mar 1 – Mar 15 | Apr 5 – Apr 19 | — | Jul 7 – Jul 28 |
| Cauliflower | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 7 – Jul 28 |
| Okra | Mar 15 – Mar 29 | May 17 – May 31 | May 17 – May 31 | — |
| Basil | Mar 15 – Mar 29 | May 3 – May 17 | — | — |
| Peas | — | — | Mar 15 – Apr 5 | Jul 21 – Aug 11 |
| Spinach | — | — | Mar 15 – Apr 5 | Aug 18 – Sep 8 |
| Radishes | — | — | Mar 22 – May 3 | Sep 1 – Sep 22 |
| Cucumbers | Mar 29 – Apr 5 | May 10 – May 17 | May 3 – May 17 | Jul 28 – Aug 11 |
| Zucchini & Summer Squash | Mar 29 – Apr 5 | — | May 3 – May 17 | Aug 4 – Aug 18 |
| Winter Squash & Pumpkins | Mar 29 – Apr 5 | — | May 3 – May 17 | — |
| Melons & Watermelon | Mar 29 – Apr 5 | May 10 – May 24 | — | — |
| Carrots | — | — | Apr 5 – May 3 | Jul 21 – Aug 4 |
| Beets | — | — | Apr 5 – May 3 | Aug 4 – Aug 18 |
| Potatoes | — | — | Apr 5 – Apr 26 | — |
| Swiss Chard | — | — | Apr 12 – May 10 | Aug 4 – Aug 18 |
| Cilantro | — | — | Apr 12 – May 3 | Aug 18 – Sep 8 |
| Green Beans | — | — | May 3 – May 24 | Jul 28 – Aug 11 |
| Sweet Corn | — | — | May 3 – May 17 | — |
| Sweet Potatoes | — | May 10 – May 31 | — | — |
| Garlic | — | — | — | Sep 29 – Nov 3 |
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 Rochelle, IL weather station, 2 km away (elevation 774 ft (236 m)).
Frost dates near Rochelle
- Creston Apr 26 · Oct 13
- Steward Apr 26 · Oct 13
- Ashton Apr 26 · Oct 13
- Chana Apr 26 · Oct 13
- Lindenwood Apr 26 · Oct 13
- Esmond Apr 26 · Oct 13
- Holcomb Apr 24 · Oct 17
- Malta Apr 24 · Oct 18
- Lee Apr 28 · Oct 10
- Davis Junction Apr 24 · Oct 17
Frequently asked questions
When is the last frost in Rochelle, IL?
The median last spring frost in Rochelle, IL is April 26. There is still about a 10% chance of frost after May 12, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Rochelle, IL?
The median first fall frost is October 13, with about a 10% chance of frost before September 29.
How long is the growing season in Rochelle, IL?
About 170 days between the median last spring frost and first fall frost.
What planting zone is Rochelle, IL?
Rochelle, IL is in USDA hardiness zone 5b.