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Frost Dates for Radom, IL

Last spring frost
Apr 7
First fall frost
Oct 26
Growing season
201 days
Hardiness zone
6b

In an average year around Radom, IL, the last spring frost (32°F) is about Apr 7 and the first fall frost is about Oct 26, giving roughly a 201-day growing season. To be safe most years, wait until Mar 24 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Radom, IL
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 4 Apr 19 Apr 6
Freeze (32°F) Apr 22 Apr 7 Mar 24
Hard (28°F) Apr 12 Mar 30 Mar 13
Severe (24°F) Apr 3 Mar 19 Mar 1
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 4 Apr 29 Apr 25 Apr 22 Apr 19 Apr 16 Apr 13 Apr 9 Apr 6
32°F Apr 22 Apr 18 Apr 13 Apr 10 Apr 7 Apr 5 Apr 2 Mar 30 Mar 24
28°F Apr 12 Apr 7 Apr 4 Apr 1 Mar 30 Mar 27 Mar 23 Mar 19 Mar 13
24°F Apr 3 Mar 31 Mar 27 Mar 22 Mar 19 Mar 15 Mar 11 Mar 7 Mar 1
20°F Mar 26 Mar 19 Mar 15 Mar 12 Mar 9 Mar 5 Mar 2 Feb 27 Feb 21
16°F Mar 17 Mar 11 Mar 7 Mar 3 Feb 28 Feb 25 Feb 21 Feb 14 Feb 7

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Radom, IL
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 4 Oct 16 Oct 27
Freeze (32°F) Oct 14 Oct 26 Nov 6
Hard (28°F) Oct 24 Nov 4 Nov 19
Severe (24°F) Nov 1 Nov 15 Dec 2
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 4 Oct 9 Oct 12 Oct 14 Oct 16 Oct 19 Oct 21 Oct 24 Oct 27
32°F Oct 14 Oct 18 Oct 22 Oct 24 Oct 26 Oct 28 Oct 31 Nov 2 Nov 6
28°F Oct 24 Oct 29 Nov 1 Nov 2 Nov 4 Nov 7 Nov 10 Nov 14 Nov 19
24°F Nov 1 Nov 5 Nov 9 Nov 12 Nov 15 Nov 18 Nov 23 Nov 27 Dec 2
20°F Nov 10 Nov 14 Nov 18 Nov 22 Nov 26 Nov 29 Dec 3 Dec 6 Dec 13
16°F Nov 18 Nov 24 Nov 28 Dec 2 Dec 6 Dec 10 Dec 14 Dec 20 Dec 27

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Nashville 1 E, Il, about 10 miles away@if(!empty($station['elevation_ft'])), at 513 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Radom, IL?

On average, the last spring frost (32°F) around Radom, IL is about Apr 7. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 24.

When is the first frost in the fall?

The first fall frost around Radom, IL typically arrives about Oct 26. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 7 on average, or Mar 24 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 201 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 62876 Planting calendar → Illinois frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026