Harman US

Frost Dates for Rantoul, KS

Last spring frost
Apr 14
First fall frost
Oct 25
Growing season
192 days
Hardiness zone
6b

In an average year around Rantoul, KS, the last spring frost (32°F) is about Apr 14 and the first fall frost is about Oct 25, giving roughly a 192-day growing season. To be safe most years, wait until Mar 31 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 - Rantoul, KS
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 6 Apr 23 Apr 9
Freeze (32°F) Apr 29 Apr 14 Mar 31
Hard (28°F) Apr 18 Apr 3 Mar 19
Severe (24°F) Apr 9 Mar 26 Mar 8
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 6 May 2 Apr 30 Apr 27 Apr 23 Apr 20 Apr 17 Apr 14 Apr 9
32°F Apr 29 Apr 23 Apr 19 Apr 16 Apr 14 Apr 11 Apr 8 Apr 5 Mar 31
28°F Apr 18 Apr 12 Apr 9 Apr 6 Apr 3 Apr 1 Mar 30 Mar 25 Mar 19
24°F Apr 9 Apr 5 Apr 1 Mar 29 Mar 26 Mar 22 Mar 18 Mar 13 Mar 8
20°F Apr 1 Mar 27 Mar 22 Mar 18 Mar 14 Mar 11 Mar 7 Mar 3 Feb 27
16°F Mar 20 Mar 15 Mar 11 Mar 8 Mar 5 Mar 2 Feb 28 Feb 23 Feb 17

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 - Rantoul, KS
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 30 Oct 15 Oct 27
Freeze (32°F) Oct 11 Oct 25 Nov 5
Hard (28°F) Oct 21 Nov 3 Nov 18
Severe (24°F) Oct 31 Nov 11 Nov 30
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 30 Oct 6 Oct 10 Oct 12 Oct 15 Oct 18 Oct 20 Oct 23 Oct 27
32°F Oct 11 Oct 16 Oct 19 Oct 22 Oct 25 Oct 27 Oct 30 Nov 1 Nov 5
28°F Oct 21 Oct 26 Oct 29 Nov 1 Nov 3 Nov 5 Nov 8 Nov 11 Nov 18
24°F Oct 31 Nov 3 Nov 5 Nov 8 Nov 11 Nov 15 Nov 18 Nov 24 Nov 30
20°F Nov 5 Nov 10 Nov 14 Nov 17 Nov 21 Nov 25 Nov 30 Dec 3 Dec 9
16°F Nov 13 Nov 19 Nov 24 Nov 28 Dec 1 Dec 5 Dec 8 Dec 14 Dec 20

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: Osawatomie, Ks, about 9.3 miles away@if(!empty($station['elevation_ft'])), at 860 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 Rantoul, KS?

On average, the last spring frost (32°F) around Rantoul, KS is about Apr 14. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 31.

When is the first frost in the fall?

The first fall frost around Rantoul, KS typically arrives about Oct 25. 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 14 on average, or Mar 31 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 192 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 66079 Planting calendar → Kansas frost dates →

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