Warsaw, IL frost dates
Last spring frostApr 10median date
First fall frostOct 27median date
Growing season200 daysfrost-free
Hardiness zone6aZone 6a
How Warsaw compares
- In 8 years out of 10, the last spring frost in Warsaw falls between March 30 and April 26, a 27-day window. The first fall frost falls between October 10 and November 7.
- The median last frost is 7 days earlier than the Illinois median of Apr 17.
- Its 200-day growing season is longer than 83% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 19 days earlier than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 117 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 30 |
| 50% (median) | April 10 |
| 10% (safe for tender plants) | April 26 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 10 |
| 50% (median) | October 27 |
| 90% (late) | November 7 |
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 Warsaw, IL
Warsaw, IL frost dates — last frost Apr 10, first frost Oct 27, zone 6a. whenisthelastfrost.com
Crop
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Start indoors: Jan 16 to Jan 30Transplant outside: Mar 13 to Mar 27
Start indoors: Jan 30 to Feb 13Transplant outside: Apr 24 to May 8
Start indoors: Jan 30 to Feb 13Transplant outside: Apr 24 to May 8
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 17 to May 1
Start indoors: Feb 13 to Feb 27Transplant outside: Mar 20 to Apr 3Sow outdoors: Mar 13 to Apr 17Plant for fall: Sep 1 to Sep 29
Start indoors: Feb 13 to Feb 27Transplant outside: Mar 13 to Mar 27Sow outdoors: Mar 13 to Mar 27Plant for fall: Aug 18 to Sep 8
Start indoors: Feb 13 to Feb 27Transplant outside: Mar 27 to Apr 10Plant for fall: Jul 21 to Aug 11
Start indoors: Feb 13 to Feb 27Transplant outside: Mar 20 to Apr 3Plant for fall: Jul 21 to Aug 11
Start indoors: Feb 13 to Feb 27Transplant outside: Mar 27 to Apr 10Plant for fall: Jul 21 to Aug 11
Start indoors: Feb 27 to Mar 13Transplant outside: May 1 to May 15Sow outdoors: May 1 to May 15
Start indoors: Feb 27 to Mar 13Transplant outside: Apr 17 to May 1
Sow outdoors: Feb 27 to Mar 20Plant for fall: Aug 4 to Aug 25
Sow outdoors: Feb 27 to Mar 20Plant for fall: Sep 1 to Sep 22
Sow outdoors: Mar 6 to Apr 17Plant for fall: Sep 15 to Oct 6
Start indoors: Mar 13 to Mar 20Transplant outside: Apr 24 to May 1Sow outdoors: Apr 17 to May 1Plant for fall: Aug 11 to Aug 25
Start indoors: Mar 13 to Mar 20Sow outdoors: Apr 17 to May 1Plant for fall: Aug 18 to Sep 1
Start indoors: Mar 13 to Mar 20Sow outdoors: Apr 17 to May 1
Start indoors: Mar 13 to Mar 20Transplant outside: Apr 24 to May 8
Sow outdoors: Mar 20 to Apr 17Plant for fall: Aug 4 to Aug 18
Sow outdoors: Mar 20 to Apr 17Plant for fall: Aug 18 to Sep 1
Sow outdoors: Mar 20 to Apr 10
Sow outdoors: Mar 27 to Apr 24Plant for fall: Aug 18 to Sep 1
Sow outdoors: Mar 27 to Apr 17Plant for fall: Sep 1 to Sep 22
Sow outdoors: Apr 17 to May 8Plant for fall: Aug 11 to Aug 25
Sow outdoors: Apr 17 to May 1
Transplant outside: Apr 24 to May 15
Plant for fall: Oct 13 to Nov 17
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Warsaw, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 16 – Jan 30 | Mar 13 – Mar 27 | — | — |
| Peppers | Jan 30 – Feb 13 | Apr 24 – May 8 | — | — |
| Eggplant | Jan 30 – Feb 13 | Apr 24 – May 8 | — | — |
| Tomatoes | Feb 13 – Feb 27 | Apr 17 – May 1 | — | — |
| Lettuce | Feb 13 – Feb 27 | Mar 20 – Apr 3 | Mar 13 – Apr 17 | Sep 1 – Sep 29 |
| Kale | Feb 13 – Feb 27 | Mar 13 – Mar 27 | Mar 13 – Mar 27 | Aug 18 – Sep 8 |
| Broccoli | Feb 13 – Feb 27 | Mar 27 – Apr 10 | — | Jul 21 – Aug 11 |
| Cabbage | Feb 13 – Feb 27 | Mar 20 – Apr 3 | — | Jul 21 – Aug 11 |
| Cauliflower | Feb 13 – Feb 27 | Mar 27 – Apr 10 | — | Jul 21 – Aug 11 |
| Okra | Feb 27 – Mar 13 | May 1 – May 15 | May 1 – May 15 | — |
| Basil | Feb 27 – Mar 13 | Apr 17 – May 1 | — | — |
| Peas | — | — | Feb 27 – Mar 20 | Aug 4 – Aug 25 |
| Spinach | — | — | Feb 27 – Mar 20 | Sep 1 – Sep 22 |
| Radishes | — | — | Mar 6 – Apr 17 | Sep 15 – Oct 6 |
| Cucumbers | Mar 13 – Mar 20 | Apr 24 – May 1 | Apr 17 – May 1 | Aug 11 – Aug 25 |
| Zucchini & Summer Squash | Mar 13 – Mar 20 | — | Apr 17 – May 1 | Aug 18 – Sep 1 |
| Winter Squash & Pumpkins | Mar 13 – Mar 20 | — | Apr 17 – May 1 | — |
| Melons & Watermelon | Mar 13 – Mar 20 | Apr 24 – May 8 | — | — |
| Carrots | — | — | Mar 20 – Apr 17 | Aug 4 – Aug 18 |
| Beets | — | — | Mar 20 – Apr 17 | Aug 18 – Sep 1 |
| Potatoes | — | — | Mar 20 – Apr 10 | — |
| Swiss Chard | — | — | Mar 27 – Apr 24 | Aug 18 – Sep 1 |
| Cilantro | — | — | Mar 27 – Apr 17 | Sep 1 – Sep 22 |
| Green Beans | — | — | Apr 17 – May 8 | Aug 11 – Aug 25 |
| Sweet Corn | — | — | Apr 17 – May 1 | — |
| Sweet Potatoes | — | Apr 24 – May 15 | — | — |
| Garlic | — | — | — | Oct 13 – Nov 17 |
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 Keokuk Lock Dam, IA weather station, 7 km away (elevation 528 ft (161 m)).
Frost dates near Warsaw
- Sutter Apr 10 · Oct 27
- Hamilton Apr 10 · Oct 27
- Elvaston Apr 10 · Oct 27
- Lima Apr 11 · Oct 23
- Basco Apr 13 · Oct 22
- Nauvoo Apr 12 · Oct 25
- West Point Apr 13 · Oct 22
- Ferris Apr 13 · Oct 22
- Carthage Apr 13 · Oct 22
- Loraine Apr 18 · Oct 21
Frequently asked questions
When is the last frost in Warsaw, IL?
The median last spring frost in Warsaw, IL is April 10. There is still about a 10% chance of frost after April 26, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Warsaw, IL?
The median first fall frost is October 27, with about a 10% chance of frost before October 10.
How long is the growing season in Warsaw, IL?
About 200 days between the median last spring frost and first fall frost.
What planting zone is Warsaw, IL?
Warsaw, IL is in USDA hardiness zone 6a.