Last spring frost
Apr 13
Frost Dates for Olathe, KS
First fall frost
Oct 24
Growing season
193 days
Hardiness zone
6b
In an average year around Olathe, KS, the last spring frost (32°F) is about Apr 13 and the first fall frost is about Oct 24, giving roughly a 193-day growing season. To be safe most years, wait until Mar 30 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 6 | Apr 23 | Apr 9 |
| Freeze (32°F) | Apr 29 | Apr 13 | Mar 30 |
| Hard (28°F) | Apr 19 | Apr 3 | Mar 16 |
| Severe (24°F) | Apr 8 | Mar 24 | Mar 5 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 6 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 20 | Apr 17 | Apr 14 | Apr 9 |
| 32°F | Apr 29 | Apr 23 | Apr 20 | Apr 17 | Apr 13 | Apr 10 | Apr 7 | Apr 4 | Mar 30 |
| 28°F | Apr 19 | Apr 13 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 28 | Mar 23 | Mar 16 |
| 24°F | Apr 8 | Apr 2 | Mar 31 | Mar 27 | Mar 24 | Mar 20 | Mar 16 | Mar 10 | Mar 5 |
| 20°F | Mar 30 | Mar 23 | Mar 19 | Mar 16 | Mar 12 | Mar 8 | Mar 5 | Mar 1 | Feb 24 |
| 16°F | Mar 21 | Mar 15 | Mar 11 | Mar 7 | Mar 4 | Feb 28 | Feb 25 | Feb 21 | Feb 14 |
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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Sep 30 | Oct 15 | Oct 27 |
| Freeze (32°F) | Oct 10 | Oct 24 | Nov 4 |
| Hard (28°F) | Oct 20 | Nov 2 | Nov 18 |
| Severe (24°F) | Oct 30 | Nov 11 | Nov 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 30 | Oct 5 | Oct 9 | Oct 13 | Oct 15 | Oct 18 | Oct 20 | Oct 23 | Oct 27 |
| 32°F | Oct 10 | Oct 16 | Oct 19 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 4 |
| 28°F | Oct 20 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 7 | Nov 11 | Nov 18 |
| 24°F | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 28 |
| 20°F | Nov 4 | Nov 10 | Nov 13 | Nov 17 | Nov 20 | Nov 25 | Nov 28 | Dec 2 | Dec 8 |
| 16°F | Nov 12 | Nov 18 | Nov 23 | Nov 26 | Nov 30 | Dec 3 | Dec 8 | Dec 14 | Dec 21 |
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
@endif These dates are computed from the nearest official weather station with long-term records: Olathe Johnson Co Ap, Ks, about 4.3 miles away@if(!empty($station['elevation_ft'])), at 1,087 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
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 Olathe, KS?
On average, the last spring frost (32°F) around Olathe, KS is about Apr 13. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 30.
When is the first frost in the fall?
The first fall frost around Olathe, KS typically arrives about Oct 24. 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 13 on average, or Mar 30 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 193 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 66061 Planting calendar → Kansas frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026