Union Hill, IL frost dates
Last spring frostApr 19median date
First fall frostOct 24median date
Growing season188 daysfrost-free
Hardiness zone5bZone 5b
How Union Hill compares
- In 8 years out of 10, the last spring frost in Union Hill falls between April 5 and May 3, a 28-day window. The first fall frost falls between October 12 and November 5.
- The median last frost is 2 days later than the Illinois median of Apr 17.
- Its 188-day growing season is longer than 51% 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 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 129 nights a year at or below 32°F.
- Compared with Joliet, IL, 45 km away, the last frost here is the same as there and the growing season is 1 day shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 5 |
| 50% (median) | April 19 |
| 10% (safe for tender plants) | May 3 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 12 |
| 50% (median) | October 24 |
| 90% (late) | November 5 |
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 Union Hill, IL
Union Hill, IL frost dates — last frost Apr 19, first frost Oct 24, zone 5b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Jan 25 to Feb 8Transplant outside: Mar 22 to Apr 5
Start indoors: Feb 8 to Feb 22Transplant outside: May 3 to May 17
Start indoors: Feb 8 to Feb 22Transplant outside: May 3 to May 17
Start indoors: Feb 22 to Mar 8Transplant outside: Apr 26 to May 10
Start indoors: Feb 22 to Mar 8Transplant outside: Mar 29 to Apr 12Sow outdoors: Mar 22 to Apr 26Plant for fall: Aug 29 to Sep 26
Start indoors: Feb 22 to Mar 8Transplant outside: Mar 22 to Apr 5Sow outdoors: Mar 22 to Apr 5Plant for fall: Aug 15 to Sep 5
Start indoors: Feb 22 to Mar 8Transplant outside: Apr 5 to Apr 19Plant for fall: Jul 18 to Aug 8
Start indoors: Feb 22 to Mar 8Transplant outside: Mar 29 to Apr 12Plant for fall: Jul 18 to Aug 8
Start indoors: Feb 22 to Mar 8Transplant outside: Apr 5 to Apr 19Plant for fall: Jul 18 to Aug 8
Start indoors: Mar 8 to Mar 22Transplant outside: May 10 to May 24Sow outdoors: May 10 to May 24
Start indoors: Mar 8 to Mar 22Transplant outside: Apr 26 to May 10
Sow outdoors: Mar 8 to Mar 29Plant for fall: Aug 1 to Aug 22
Sow outdoors: Mar 8 to Mar 29Plant for fall: Aug 29 to Sep 19
Sow outdoors: Mar 15 to Apr 26Plant for fall: Sep 12 to Oct 3
Start indoors: Mar 22 to Mar 29Transplant outside: May 3 to May 10Sow outdoors: Apr 26 to May 10Plant for fall: Aug 8 to Aug 22
Start indoors: Mar 22 to Mar 29Sow outdoors: Apr 26 to May 10Plant for fall: Aug 15 to Aug 29
Start indoors: Mar 22 to Mar 29Sow outdoors: Apr 26 to May 10
Start indoors: Mar 22 to Mar 29Transplant outside: May 3 to May 17
Sow outdoors: Mar 29 to Apr 26Plant for fall: Aug 1 to Aug 15
Sow outdoors: Mar 29 to Apr 26Plant for fall: Aug 15 to Aug 29
Sow outdoors: Mar 29 to Apr 19
Sow outdoors: Apr 5 to May 3Plant for fall: Aug 15 to Aug 29
Sow outdoors: Apr 5 to Apr 26Plant for fall: Aug 29 to Sep 19
Sow outdoors: Apr 26 to May 17Plant for fall: Aug 8 to Aug 22
Sow outdoors: Apr 26 to May 10
Transplant outside: May 3 to May 24
Plant for fall: Oct 10 to Nov 14
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Union Hill, IL
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 25 – Feb 8 | Mar 22 – Apr 5 | — | — |
| Peppers | Feb 8 – Feb 22 | May 3 – May 17 | — | — |
| Eggplant | Feb 8 – Feb 22 | May 3 – May 17 | — | — |
| Tomatoes | Feb 22 – Mar 8 | Apr 26 – May 10 | — | — |
| Lettuce | Feb 22 – Mar 8 | Mar 29 – Apr 12 | Mar 22 – Apr 26 | Aug 29 – Sep 26 |
| Kale | Feb 22 – Mar 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | Aug 15 – Sep 5 |
| Broccoli | Feb 22 – Mar 8 | Apr 5 – Apr 19 | — | Jul 18 – Aug 8 |
| Cabbage | Feb 22 – Mar 8 | Mar 29 – Apr 12 | — | Jul 18 – Aug 8 |
| Cauliflower | Feb 22 – Mar 8 | Apr 5 – Apr 19 | — | Jul 18 – Aug 8 |
| Okra | Mar 8 – Mar 22 | May 10 – May 24 | May 10 – May 24 | — |
| Basil | Mar 8 – Mar 22 | Apr 26 – May 10 | — | — |
| Peas | — | — | Mar 8 – Mar 29 | Aug 1 – Aug 22 |
| Spinach | — | — | Mar 8 – Mar 29 | Aug 29 – Sep 19 |
| Radishes | — | — | Mar 15 – Apr 26 | Sep 12 – Oct 3 |
| Cucumbers | Mar 22 – Mar 29 | May 3 – May 10 | Apr 26 – May 10 | Aug 8 – Aug 22 |
| Zucchini & Summer Squash | Mar 22 – Mar 29 | — | Apr 26 – May 10 | Aug 15 – Aug 29 |
| Winter Squash & Pumpkins | Mar 22 – Mar 29 | — | Apr 26 – May 10 | — |
| Melons & Watermelon | Mar 22 – Mar 29 | May 3 – May 17 | — | — |
| Carrots | — | — | Mar 29 – Apr 26 | Aug 1 – Aug 15 |
| Beets | — | — | Mar 29 – Apr 26 | Aug 15 – Aug 29 |
| Potatoes | — | — | Mar 29 – Apr 19 | — |
| Swiss Chard | — | — | Apr 5 – May 3 | Aug 15 – Aug 29 |
| Cilantro | — | — | Apr 5 – Apr 26 | Aug 29 – Sep 19 |
| Green Beans | — | — | Apr 26 – May 17 | Aug 8 – Aug 22 |
| Sweet Corn | — | — | Apr 26 – May 10 | — |
| Sweet Potatoes | — | May 3 – May 24 | — | — |
| Garlic | — | — | — | Oct 10 – Nov 14 |
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 Kankakee Metro Wastewater, IL weather station, 22 km away (elevation 600 ft (183 m)).
Frost dates near Union Hill
- Reddick Apr 27 · Oct 15
- Essex Apr 27 · Oct 15
- Buckingham Apr 27 · Oct 15
- Herscher Apr 19 · Oct 24
- Bonfield Apr 19 · Oct 24
- South Wilmington Apr 27 · Oct 15
- Cabery Apr 27 · Oct 15
- Campus Apr 27 · Oct 15
- Braceville Apr 27 · Oct 15
- Gardner Apr 27 · Oct 15
Frequently asked questions
When is the last frost in Union Hill, IL?
The median last spring frost in Union Hill, IL is April 19. There is still about a 10% chance of frost after May 3, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Union Hill, IL?
The median first fall frost is October 24, with about a 10% chance of frost before October 12.
How long is the growing season in Union Hill, IL?
About 188 days between the median last spring frost and first fall frost.
What planting zone is Union Hill, IL?
Union Hill, IL is in USDA hardiness zone 5b.