Peoria, Illinois: planting zone & frost dates
Peoria is in USDA plant hardiness zone 6a, where the average coldest winter night reaches -10 to -5°F (-23.3 to -20.6°C). The typical last spring frost is around Apr 23 and the first fall frost around Oct 18.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | May 4 | Oct 9 |
| Typical planning date (30% risk) | Apr 23 | Oct 18 |
| Median (50%) | Apr 16 | Oct 23 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station PEORIA GTR PEORIA AP, IL (USW00014842), 6.8 mi (10.9 km) from the city center and 66 ft lower than the city center (-20 m). Record used for the 1991–2020 normals: 30 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Peoria
Peoria spans more than one half-zone. Share of the city's land area by zone (via its 10 ZIP codes): 6a (95%), 5b (5%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
Vegetable planting calendar for Peoria
Dates are counted from the 30%-risk frost dates above (last frost Apr 23, first frost Oct 18). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Feb 26 – Mar 12 | Apr 30 – May 14 | — | — |
| Pepper | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Lettuce | Mar 12 – Mar 26 | Apr 9 – Apr 30 | Mar 26 – May 7 | Aug 9 – Sep 6 |
| Green Beans | — | — | Apr 30 – Jun 4 | Jul 26 – Aug 9 |
| Sweet Corn | — | — | Apr 30 – May 28 | — |
| Zucchini & Summer Squash | Mar 26 – Apr 2 | Apr 30 – May 14 | Apr 30 – May 21 | Jul 26 – Aug 9 |
| Cucumber | Mar 26 – Apr 2 | May 7 – May 14 | Apr 30 – May 21 | Jul 26 – Aug 9 |
| Carrot | — | — | Apr 2 – May 7 | Jul 26 – Aug 9 |
| Onion | Jan 29 – Feb 12 | Mar 26 – Apr 9 | — | — |
| Potato | — | Mar 26 – Apr 16 | — | — |
| Basil | Mar 12 – Mar 26 | May 7 – May 21 | May 7 – May 28 | — |
| Spinach | — | — | Mar 12 – Apr 9 | Aug 23 – Sep 20 |
| Kale | Feb 26 – Mar 12 | Mar 26 – Apr 16 | Mar 26 – Apr 16 | Aug 9 – Sep 6 |
| Broccoli | Feb 26 – Mar 12 | Apr 9 – Apr 30 | — | Jul 26 – Aug 9 |
| Peas | — | — | Mar 12 – Apr 2 | Aug 9 – Aug 23 |
| Eggplant | Feb 12 – Feb 26 | May 7 – May 21 | — | — |
| Cabbage | Feb 26 – Mar 12 | Mar 26 – Apr 9 | — | Jul 26 – Aug 9 |
| Radish | — | — | Mar 19 – May 7 | Sep 6 – Oct 4 |
| Strawberry | — | Mar 26 – Apr 16 | — | — |
| Beets | — | — | Apr 2 – May 14 | Aug 9 – Aug 23 |
Nearby cities in Illinois
- Bloomington — zone 6a, last frost May 1, first frost Oct 11
- Springfield — zone 6a, last frost Apr 20, first frost Oct 17
- Champaign — zone 6a, last frost Apr 21, first frost Oct 19
- Rockford — zone 5b, last frost Apr 30, first frost Oct 12
- Joliet — zone 6a, last frost Apr 26, first frost Oct 20
- Aurora — zone 5b, last frost Apr 25, first frost Oct 18
More: all Illinois cities · other zone 6a cities: Chicago, IL, Denver, CO, Milwaukee, WI, Colorado Springs, CO, Omaha, NE, Aurora, CO, Lincoln, NE, Fort Wayne, IN
Peoria gardening questions
When is the last frost in Peoria, IL?
Plan around Apr 23. At NOAA's Peoria Gtr Peoria Airport, IL station, 6.8 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Apr 16, and after May 4 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Apr 5. The 90% and 10% dates are 32 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Peoria, IL?
Start seeds indoors Feb 26 – Mar 12 and set transplants outside Apr 30 – May 14, once nights stay above 50°F and the soil is near 60°F. That leaves 178 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.
How long is the growing season in Peoria?
About 189 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 167 days, and in 1 year in 10 it runs 209 days or more. In fall there is a 10% chance of frost by Oct 9 and a 30% chance by Oct 18. That ranks 4th longest of 14 Illinois cities on this site.
When should I plant a fall garden in Peoria?
Count back from the first fall frost (Oct 18): transplant broccoli Jul 26 – Aug 9; sow kale Aug 9 – Sep 6; sow lettuce Aug 9 – Sep 6; sow radishes Sep 6 – Oct 4. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 2. How the math works: succession and fall planting.
Did Peoria's hardiness zone change on the 2023 map?
Yes. Most of Peoria was zone 5b on the 2012 map and is zone 6a on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
Is all of Peoria in zone 6a?
No. Zone 6a covers about 95% of the city's land; the rest is in 5b (5%), measured across the city's 10 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.