Growing season
85 days
Frost Dates for Juliaetta, ID
Hardiness zone
7b
Frost normals for this location are limited (the nearest long-term weather station may not report all thresholds). The available data is shown below.
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%) |
|---|---|---|---|
| Hard (28°F) | Jun 8 | May 14 | Apr 27 |
| Severe (24°F) | May 12 | Apr 22 | Mar 24 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 28°F | Jun 8 | May 29 | May 24 | May 18 | May 14 | May 10 | May 6 | May 2 | Apr 27 |
| 24°F | May 12 | May 5 | May 1 | Apr 26 | Apr 22 | Apr 16 | Apr 10 | Apr 1 | Mar 24 |
| 20°F | Apr 21 | Apr 7 | Mar 31 | Mar 24 | Mar 18 | Mar 13 | Mar 9 | Mar 5 | Feb 28 |
| 16°F | Mar 21 | Mar 15 | Mar 10 | Mar 6 | Mar 2 | Feb 27 | Feb 23 | Feb 16 | 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Hard (28°F) | Sep 6 | Sep 23 | Oct 9 |
| Severe (24°F) | Sep 20 | Oct 6 | Oct 30 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 28°F | Sep 6 | Sep 12 | Sep 16 | Sep 20 | Sep 23 | Sep 26 | Sep 29 | Oct 3 | Oct 9 |
| 24°F | Sep 20 | Sep 27 | Sep 30 | Oct 3 | Oct 6 | Oct 10 | Oct 16 | Oct 21 | Oct 30 |
| 20°F | Oct 4 | Oct 11 | Oct 17 | Oct 21 | Oct 25 | Oct 31 | Nov 5 | Nov 13 | Nov 22 |
| 16°F | Oct 18 | Oct 27 | Nov 1 | Nov 6 | Nov 12 | Nov 18 | Nov 24 | Nov 29 | Dec 7 |
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: Moscow U Of I, Id, about 16.9 miles away@if(!empty($station['elevation_ft'])), at 2,660 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
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 85 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 83535 Planting calendar → Idaho frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026