Last spring frost
May 15
Frost Dates for Oakley, ID
First fall frost
Oct 2
Growing season
137 days
Hardiness zone
6a
In an average year around Oakley, ID, the last spring frost (32°F) is about May 15 and the first fall frost is about Oct 2, giving roughly a 137-day growing season. To be safe most years, wait until Apr 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) | Jun 19 | Jun 2 | May 16 |
| Freeze (32°F) | Jun 6 | May 15 | Apr 30 |
| Hard (28°F) | May 15 | Apr 30 | Apr 13 |
| Severe (24°F) | May 4 | Apr 14 | Mar 22 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 19 | Jun 14 | Jun 10 | Jun 6 | Jun 2 | May 31 | May 26 | May 21 | May 16 |
| 32°F | Jun 6 | May 30 | May 23 | May 18 | May 15 | May 12 | May 8 | May 4 | Apr 30 |
| 28°F | May 15 | May 9 | May 6 | May 3 | Apr 30 | Apr 27 | Apr 24 | Apr 19 | Apr 13 |
| 24°F | May 4 | Apr 28 | Apr 22 | Apr 19 | Apr 14 | Apr 10 | Apr 5 | Mar 31 | Mar 22 |
| 20°F | Apr 22 | Apr 12 | Apr 5 | Apr 1 | Mar 27 | Mar 21 | Mar 15 | Mar 8 | Mar 2 |
| 16°F | Mar 28 | Mar 18 | Mar 12 | Mar 7 | Mar 3 | Feb 28 | Feb 23 | Feb 17 | Feb 11 |
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 5 | Sep 22 | Oct 6 |
| Freeze (32°F) | Sep 16 | Oct 2 | Oct 17 |
| Hard (28°F) | Sep 30 | Oct 16 | Nov 1 |
| Severe (24°F) | Oct 13 | Oct 28 | Nov 14 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 5 | Sep 11 | Sep 16 | Sep 19 | Sep 22 | Sep 24 | Sep 27 | Oct 1 | Oct 6 |
| 32°F | Sep 16 | Sep 22 | Sep 26 | Sep 29 | Oct 2 | Oct 6 | Oct 10 | Oct 13 | Oct 17 |
| 28°F | Sep 30 | Oct 5 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 23 | Oct 26 | Nov 1 |
| 24°F | Oct 13 | Oct 18 | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 3 | Nov 6 | Nov 14 |
| 20°F | Oct 22 | Oct 27 | Oct 31 | Nov 3 | Nov 6 | Nov 10 | Nov 14 | Nov 18 | Nov 24 |
| 16°F | Oct 29 | Nov 4 | Nov 10 | Nov 14 | Nov 18 | Nov 21 | Nov 24 | Nov 29 | Dec 5 |
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: Oakley, Id, about 15.8 miles away@if(!empty($station['elevation_ft'])), at 4,559 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 Oakley, ID?
On average, the last spring frost (32°F) around Oakley, ID is about May 15. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 30.
When is the first frost in the fall?
The first fall frost around Oakley, ID typically arrives about Oct 2. 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 May 15 on average, or Apr 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 137 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 83312 Planting calendar → Idaho frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026