Johnston City, IL frost dates
Last spring frostApr 4median date
First fall frostOct 28median date
Growing season207 daysfrost-free
Hardiness zone7aZone 7a
How Johnston City compares
- In 8 years out of 10, the last spring frost in Johnston City falls between March 19 and April 21, a 33-day window. The first fall frost falls between October 15 and November 10.
- The median last frost is 13 days earlier than the Illinois median of Apr 17.
- Its 207-day growing season is longer than 95% of the 1,287 Illinois places with a regular frost season (state median 187 days).
- The last frost is 12 days earlier than the zone 7a median of Apr 16. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7a chart.
- The weather station records an average of 93 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 19 |
| 50% (median) | April 4 |
| 10% (safe for tender plants) | April 21 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 15 |
| 50% (median) | October 28 |
| 90% (late) | November 10 |
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 Johnston City, IL
Johnston City, IL frost dates — last frost Apr 4, first frost Oct 28, zone 7a. whenisthelastfrost.com
Crop
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Start indoors: Jan 10 to Jan 24Transplant outside: Mar 7 to Mar 21
Start indoors: Jan 24 to Feb 7Transplant outside: Apr 18 to May 2
Start indoors: Jan 24 to Feb 7Transplant outside: Apr 18 to May 2
Start indoors: Feb 7 to Feb 21Transplant outside: Apr 11 to Apr 25
Start indoors: Feb 7 to Feb 21Transplant outside: Mar 14 to Mar 28Sow outdoors: Mar 7 to Apr 11Plant for fall: Sep 2 to Sep 30
Start indoors: Feb 7 to Feb 21Transplant outside: Mar 7 to Mar 21Sow outdoors: Mar 7 to Mar 21Plant for fall: Aug 19 to Sep 9
Start indoors: Feb 7 to Feb 21Transplant outside: Mar 21 to Apr 4Plant for fall: Jul 22 to Aug 12
Start indoors: Feb 7 to Feb 21Transplant outside: Mar 14 to Mar 28Plant for fall: Jul 22 to Aug 12
Start indoors: Feb 7 to Feb 21Transplant outside: Mar 21 to Apr 4Plant for fall: Jul 22 to Aug 12
Start indoors: Feb 21 to Mar 7Transplant outside: Apr 25 to May 9Sow outdoors: Apr 25 to May 9
Start indoors: Feb 21 to Mar 7Transplant outside: Apr 11 to Apr 25
Sow outdoors: Feb 21 to Mar 14Plant for fall: Aug 5 to Aug 26
Sow outdoors: Feb 21 to Mar 14Plant for fall: Sep 2 to Sep 23
Sow outdoors: Feb 28 to Apr 11Plant for fall: Sep 16 to Oct 7
Start indoors: Mar 7 to Mar 14Transplant outside: Apr 18 to Apr 25Sow outdoors: Apr 11 to Apr 25Plant for fall: Aug 12 to Aug 26
Start indoors: Mar 7 to Mar 14Sow outdoors: Apr 11 to Apr 25Plant for fall: Aug 19 to Sep 2
Start indoors: Mar 7 to Mar 14Sow outdoors: Apr 11 to Apr 25
Start indoors: Mar 7 to Mar 14Transplant outside: Apr 18 to May 2
Sow outdoors: Mar 14 to Apr 11Plant for fall: Aug 5 to Aug 19
Sow outdoors: Mar 14 to Apr 11Plant for fall: Aug 19 to Sep 2
Sow outdoors: Mar 14 to Apr 4
Sow outdoors: Mar 21 to Apr 18Plant for fall: Aug 19 to Sep 2
Sow outdoors: Mar 21 to Apr 11Plant for fall: Sep 2 to Sep 23
Sow outdoors: Apr 11 to May 2Plant for fall: Aug 12 to Aug 26
Sow outdoors: Apr 11 to Apr 25
Transplant outside: Apr 18 to May 9
Plant for fall: Oct 14 to Nov 18
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Johnston City, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 10 – Jan 24 | Mar 7 – Mar 21 | — | — |
| Peppers | Jan 24 – Feb 7 | Apr 18 – May 2 | — | — |
| Eggplant | Jan 24 – Feb 7 | Apr 18 – May 2 | — | — |
| Tomatoes | Feb 7 – Feb 21 | Apr 11 – Apr 25 | — | — |
| Lettuce | Feb 7 – Feb 21 | Mar 14 – Mar 28 | Mar 7 – Apr 11 | Sep 2 – Sep 30 |
| Kale | Feb 7 – Feb 21 | Mar 7 – Mar 21 | Mar 7 – Mar 21 | Aug 19 – Sep 9 |
| Broccoli | Feb 7 – Feb 21 | Mar 21 – Apr 4 | — | Jul 22 – Aug 12 |
| Cabbage | Feb 7 – Feb 21 | Mar 14 – Mar 28 | — | Jul 22 – Aug 12 |
| Cauliflower | Feb 7 – Feb 21 | Mar 21 – Apr 4 | — | Jul 22 – Aug 12 |
| Okra | Feb 21 – Mar 7 | Apr 25 – May 9 | Apr 25 – May 9 | — |
| Basil | Feb 21 – Mar 7 | Apr 11 – Apr 25 | — | — |
| Peas | — | — | Feb 21 – Mar 14 | Aug 5 – Aug 26 |
| Spinach | — | — | Feb 21 – Mar 14 | Sep 2 – Sep 23 |
| Radishes | — | — | Feb 28 – Apr 11 | Sep 16 – Oct 7 |
| Cucumbers | Mar 7 – Mar 14 | Apr 18 – Apr 25 | Apr 11 – Apr 25 | Aug 12 – Aug 26 |
| Zucchini & Summer Squash | Mar 7 – Mar 14 | — | Apr 11 – Apr 25 | Aug 19 – Sep 2 |
| Winter Squash & Pumpkins | Mar 7 – Mar 14 | — | Apr 11 – Apr 25 | — |
| Melons & Watermelon | Mar 7 – Mar 14 | Apr 18 – May 2 | — | — |
| Carrots | — | — | Mar 14 – Apr 11 | Aug 5 – Aug 19 |
| Beets | — | — | Mar 14 – Apr 11 | Aug 19 – Sep 2 |
| Potatoes | — | — | Mar 14 – Apr 4 | — |
| Swiss Chard | — | — | Mar 21 – Apr 18 | Aug 19 – Sep 2 |
| Cilantro | — | — | Mar 21 – Apr 11 | Sep 2 – Sep 23 |
| Green Beans | — | — | Apr 11 – May 2 | Aug 12 – Aug 26 |
| Sweet Corn | — | — | Apr 11 – Apr 25 | — |
| Sweet Potatoes | — | Apr 18 – May 9 | — | — |
| Garlic | — | — | — | Oct 14 – Nov 18 |
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 Benton 2 N, IL weather station, 23 km away (elevation 446 ft (136 m)).
Frost dates near Johnston City
- Freeman Spur Apr 4 · Oct 27
- West Frankfort Apr 4 · Oct 28
- Herrin Apr 9 · Oct 22
- Pittsburg Apr 7 · Oct 26
- Energy Apr 9 · Oct 22
- Marion Apr 9 · Oct 22
- Orient Apr 4 · Oct 27
- Zeigler Apr 6 · Oct 22
- Colp Apr 9 · Oct 22
- Thompsonville Apr 4 · Oct 28
Frequently asked questions
When is the last frost in Johnston City, IL?
The median last spring frost in Johnston City, IL is April 4. There is still about a 10% chance of frost after April 21, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Johnston City, IL?
The median first fall frost is October 28, with about a 10% chance of frost before October 15.
How long is the growing season in Johnston City, IL?
About 207 days between the median last spring frost and first fall frost.
What planting zone is Johnston City, IL?
Johnston City, IL is in USDA hardiness zone 7a.