Last spring frost
Jun 9
Frost Dates for Old Station, CA
First fall frost
Sep 21
Growing season
102 days
Hardiness zone
7a
In an average year around Old Station, CA, the last spring frost (32°F) is about Jun 9 and the first fall frost is about Sep 21, giving roughly a 102-day growing season. To be safe most years, wait until May 21 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%) |
|---|---|---|---|
| Freeze (32°F) | Jun 27 | Jun 9 | May 21 |
| Hard (28°F) | Jun 10 | May 22 | Apr 30 |
| Severe (24°F) | May 23 | Apr 29 | Apr 13 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 32°F | Jun 27 | Jun 21 | Jun 16 | Jun 12 | Jun 9 | Jun 6 | Jun 3 | May 29 | May 21 |
| 28°F | Jun 10 | Jun 4 | May 31 | May 27 | May 22 | May 16 | May 12 | May 6 | Apr 30 |
| 24°F | May 23 | May 14 | May 6 | May 1 | Apr 29 | Apr 26 | Apr 22 | Apr 18 | Apr 13 |
| 20°F | May 5 | Apr 27 | Apr 22 | Apr 18 | Apr 16 | Apr 13 | Apr 10 | Apr 6 | Apr 2 |
| 16°F | Apr 23 | Apr 16 | Apr 12 | Apr 8 | Apr 5 | Apr 1 | Mar 25 | Mar 16 | Mar 10 |
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%) |
|---|---|---|---|
| Freeze (32°F) | Sep 1 | Sep 21 | Oct 11 |
| Hard (28°F) | Sep 18 | Oct 11 | Oct 31 |
| Severe (24°F) | Oct 7 | Oct 29 | Nov 14 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 32°F | Sep 1 | Sep 6 | Sep 11 | Sep 16 | Sep 21 | Sep 26 | Sep 30 | Oct 4 | Oct 11 |
| 28°F | Sep 18 | Sep 28 | Oct 2 | Oct 7 | Oct 11 | Oct 15 | Oct 19 | Oct 24 | Oct 31 |
| 24°F | Oct 7 | Oct 16 | Oct 21 | Oct 26 | Oct 29 | Nov 1 | Nov 5 | Nov 9 | Nov 14 |
| 20°F | Oct 26 | Nov 1 | Nov 4 | Nov 8 | Nov 11 | Nov 15 | Nov 18 | Nov 22 | Nov 27 |
| 16°F | Nov 6 | Nov 12 | Nov 16 | Nov 19 | Nov 23 | Nov 26 | Nov 30 | Dec 3 | Dec 9 |
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: Manzanita Lake, Ca, about 12.3 miles away@if(!empty($station['elevation_ft'])), at 5,750 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 Old Station, CA?
On average, the last spring frost (32°F) around Old Station, CA is about Jun 9. In cooler years it can run later, so for a safer bet many gardeners wait until May 21.
When is the first frost in the fall?
The first fall frost around Old Station, CA typically arrives about Sep 21. 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 Jun 9 on average, or May 21 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 102 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 96071 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026