Last spring frost
Mar 21
Frost Dates for Newberg, OR
First fall frost
Nov 22
Growing season
241 days
Hardiness zone
8b
In an average year around Newberg, OR, the last spring frost (32°F) is about Mar 21 and the first fall frost is about Nov 22, giving roughly a 241-day growing season. To be safe most years, wait until Feb 23 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 21 | Mar 30 |
| Freeze (32°F) | Apr 19 | Mar 21 | Feb 23 |
| Hard (28°F) | Mar 11 | Feb 15 | Jan 3 |
| Severe (24°F) | Feb 19 | Jan 16 | Dec 11 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 6 | May 1 | Apr 28 | Apr 26 | Apr 21 | Apr 16 | Apr 11 | Apr 5 | Mar 30 |
| 32°F | Apr 19 | Apr 10 | Apr 2 | Mar 28 | Mar 21 | Mar 15 | Mar 9 | Mar 1 | Feb 23 |
| 28°F | Mar 11 | Mar 2 | Feb 25 | Feb 20 | Feb 15 | Feb 9 | Feb 2 | Jan 21 | Jan 3 |
| 24°F | Feb 19 | Feb 12 | Feb 1 | Jan 26 | Jan 16 | Jan 9 | Jan 1 | Dec 23 | Dec 11 |
| 20°F | Feb 18 | Feb 7 | Jan 28 | Jan 14 | Jan 5 | Dec 31 | Dec 23 | Dec 15 | Dec 8 |
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 20 | Nov 3 | Nov 22 |
| Freeze (32°F) | Nov 4 | Nov 22 | Dec 12 |
| Hard (28°F) | Nov 15 | Dec 10 | Jan 12 |
| Severe (24°F) | Dec 1 | Dec 27 | Feb 7 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 20 | Oct 25 | Oct 29 | Oct 31 | Nov 3 | Nov 7 | Nov 11 | Nov 16 | Nov 22 |
| 32°F | Nov 4 | Nov 9 | Nov 12 | Nov 17 | Nov 22 | Nov 25 | Nov 29 | Dec 4 | Dec 12 |
| 28°F | Nov 15 | Nov 25 | Dec 1 | Dec 6 | Dec 10 | Dec 16 | Dec 22 | Dec 30 | Jan 12 |
| 24°F | Dec 1 | Dec 7 | Dec 12 | Dec 19 | Dec 27 | Jan 1 | Jan 9 | Jan 22 | Feb 7 |
| 20°F | Dec 6 | Dec 13 | Dec 19 | Dec 27 | Jan 1 | Jan 6 | Jan 15 | Feb 1 | Feb 16 |
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: Rex 1 S, Or, about 3.9 miles away@if(!empty($station['elevation_ft'])), at 515 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 Newberg, OR?
On average, the last spring frost (32°F) around Newberg, OR is about Mar 21. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 23.
When is the first frost in the fall?
The first fall frost around Newberg, OR typically arrives about Nov 22. 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 21 on average, or Feb 23 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 241 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 97132 Planting calendar → Oregon frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026