Last spring frost
Mar 29
Frost Dates for Marion, OR
First fall frost
Nov 6
Growing season
222 days
Hardiness zone
8b
In an average year around Marion, OR, the last spring frost (32°F) is about Mar 29 and the first fall frost is about Nov 6, giving roughly a 222-day growing season. To be safe most years, wait until Mar 5 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 12 | Apr 26 | Apr 5 |
| Freeze (32°F) | Apr 18 | Mar 29 | Mar 5 |
| Hard (28°F) | Mar 26 | Mar 1 | Feb 1 |
| Severe (24°F) | Mar 1 | Jan 31 | Dec 17 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 12 | May 6 | May 2 | Apr 30 | Apr 26 | Apr 22 | Apr 18 | Apr 12 | Apr 5 |
| 32°F | Apr 18 | Apr 9 | Apr 4 | Mar 31 | Mar 29 | Mar 25 | Mar 20 | Mar 14 | Mar 5 |
| 28°F | Mar 26 | Mar 19 | Mar 13 | Mar 7 | Mar 1 | Feb 26 | Feb 20 | Feb 13 | Feb 1 |
| 24°F | Mar 1 | Feb 23 | Feb 15 | Feb 8 | Jan 31 | Jan 20 | Jan 10 | Jan 1 | Dec 17 |
| 20°F | Feb 10 | Feb 1 | Jan 21 | Jan 10 | Jan 3 | Dec 30 | Dec 22 | Dec 14 | Dec 3 |
| 16°F | Feb 7 | Jan 28 | Jan 9 | Jan 1 | Dec 29 | Dec 24 | Dec 20 | Dec 15 | Dec 9 |
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) | Oct 4 | Oct 22 | Nov 10 |
| Freeze (32°F) | Oct 20 | Nov 6 | Nov 26 |
| Hard (28°F) | Nov 1 | Nov 22 | Dec 18 |
| Severe (24°F) | Nov 14 | Dec 10 | Jan 17 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 4 | Oct 11 | Oct 15 | Oct 18 | Oct 22 | Oct 25 | Oct 28 | Nov 1 | Nov 10 |
| 32°F | Oct 20 | Oct 26 | Oct 30 | Nov 2 | Nov 6 | Nov 10 | Nov 14 | Nov 20 | Nov 26 |
| 28°F | Nov 1 | Nov 7 | Nov 12 | Nov 17 | Nov 22 | Nov 27 | Dec 2 | Dec 9 | Dec 18 |
| 24°F | Nov 14 | Nov 23 | Nov 29 | Dec 5 | Dec 10 | Dec 17 | Dec 25 | Jan 3 | Jan 17 |
| 20°F | Nov 23 | Dec 2 | Dec 8 | Dec 12 | Dec 21 | Dec 27 | Jan 1 | Jan 12 | Feb 1 |
| 16°F | Dec 5 | Dec 9 | Dec 14 | Dec 20 | Dec 23 | Dec 29 | Jan 1 | Jan 15 | Feb 2 |
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: Stayton, Or, about 5.7 miles away@if(!empty($station['elevation_ft'])), at 425 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 Marion, OR?
On average, the last spring frost (32°F) around Marion, OR is about Mar 29. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 5.
When is the first frost in the fall?
The first fall frost around Marion, OR typically arrives about Nov 6. 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 Mar 29 on average, or Mar 5 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 222 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 97392 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026