Last spring frost
Apr 26
Frost Dates for Stanfield, OR
First fall frost
Oct 10
Growing season
167 days
Hardiness zone
7a
In an average year around Stanfield, OR, the last spring frost (32°F) is about Apr 26 and the first fall frost is about Oct 10, giving roughly a 167-day growing season. To be safe most years, wait until Apr 9 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 22 | May 8 | Apr 26 |
| Freeze (32°F) | May 10 | Apr 26 | Apr 9 |
| Hard (28°F) | Apr 29 | Apr 9 | Mar 20 |
| Severe (24°F) | Apr 11 | Mar 18 | Feb 25 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 22 | May 17 | May 14 | May 11 | May 8 | May 6 | May 3 | Apr 30 | Apr 26 |
| 32°F | May 10 | May 6 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 20 | Apr 15 | Apr 9 |
| 28°F | Apr 29 | Apr 21 | Apr 17 | Apr 13 | Apr 9 | Apr 5 | Apr 1 | Mar 28 | Mar 20 |
| 24°F | Apr 11 | Apr 2 | Mar 28 | Mar 24 | Mar 18 | Mar 13 | Mar 8 | Mar 4 | Feb 25 |
| 20°F | Mar 21 | Mar 12 | Mar 6 | Mar 2 | Feb 28 | Feb 23 | Feb 17 | Feb 11 | Jan 28 |
| 16°F | Mar 5 | Feb 28 | Feb 24 | Feb 18 | Feb 12 | Feb 5 | Jan 28 | Jan 14 | Jan 1 |
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 12 | Sep 28 | Oct 12 |
| Freeze (32°F) | Sep 25 | Oct 10 | Oct 26 |
| Hard (28°F) | Oct 4 | Oct 24 | Nov 7 |
| Severe (24°F) | Oct 17 | Nov 3 | Nov 28 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 12 | Sep 19 | Sep 22 | Sep 26 | Sep 28 | Oct 1 | Oct 4 | Oct 7 | Oct 12 |
| 32°F | Sep 25 | Oct 1 | Oct 3 | Oct 7 | Oct 10 | Oct 14 | Oct 17 | Oct 22 | Oct 26 |
| 28°F | Oct 4 | Oct 10 | Oct 15 | Oct 20 | Oct 24 | Oct 27 | Oct 29 | Nov 2 | Nov 7 |
| 24°F | Oct 17 | Oct 23 | Oct 28 | Nov 1 | Nov 3 | Nov 7 | Nov 12 | Nov 19 | Nov 28 |
| 20°F | Oct 26 | Nov 1 | Nov 7 | Nov 12 | Nov 18 | Nov 24 | Nov 30 | Dec 8 | Dec 18 |
| 16°F | Nov 3 | Nov 12 | Nov 21 | Nov 27 | Dec 5 | Dec 10 | Dec 19 | Dec 31 | Jan 17 |
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: Hermiston Muni Ap, Or, about 5.5 miles away@if(!empty($station['elevation_ft'])), at 641 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 Stanfield, OR?
On average, the last spring frost (32°F) around Stanfield, OR is about Apr 26. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 9.
When is the first frost in the fall?
The first fall frost around Stanfield, OR typically arrives about Oct 10. 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 26 on average, or Apr 9 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 167 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 97875 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026