Last spring frost
Feb 2
Frost Dates for San Diego, CA
First fall frost
Dec 7
Growing season
309 days
Hardiness zone
10a
In an average year around San Diego, CA, the last spring frost (32°F) is about Feb 2 and the first fall frost is about Dec 7, giving roughly a 309-day growing season. To be safe most years, wait until Dec 31 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) | Apr 5 | Mar 5 | Jan 30 |
| Freeze (32°F) | Mar 4 | Feb 2 | Dec 31 |
| Hard (28°F) | Feb 7 | Jan 5 | Dec 15 |
| Severe (24°F) | Jan 17 | Dec 28 | Dec 9 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 5 | Mar 28 | Mar 20 | Mar 12 | Mar 5 | Feb 28 | Feb 23 | Feb 13 | Jan 30 |
| 32°F | Mar 4 | Feb 25 | Feb 17 | Feb 8 | Feb 2 | Jan 26 | Jan 17 | Jan 9 | Dec 31 |
| 28°F | Feb 7 | Jan 30 | Jan 18 | Jan 11 | Jan 5 | Dec 31 | Dec 29 | Dec 22 | Dec 15 |
| 24°F | Jan 17 | Jan 9 | Jan 2 | Dec 30 | Dec 28 | Dec 25 | Dec 21 | Dec 17 | 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) | Nov 6 | Nov 23 | Dec 11 |
| Freeze (32°F) | Nov 22 | Dec 7 | Jan 1 |
| Hard (28°F) | Dec 2 | Dec 19 | Jan 14 |
| Severe (24°F) | Dec 5 | Dec 24 | Jan 10 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 6 | Nov 12 | Nov 16 | Nov 20 | Nov 23 | Nov 28 | Dec 1 | Dec 4 | Dec 11 |
| 32°F | Nov 22 | Nov 28 | Dec 1 | Dec 4 | Dec 7 | Dec 13 | Dec 17 | Dec 24 | Jan 1 |
| 28°F | Dec 2 | Dec 6 | Dec 10 | Dec 15 | Dec 19 | Dec 24 | Dec 30 | Jan 3 | Jan 14 |
| 24°F | Dec 5 | Dec 10 | Dec 14 | Dec 19 | Dec 24 | Dec 26 | Dec 29 | Jan 2 | Jan 10 |
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: San Pasqual Animal Pk, Ca, about 2.4 miles away@if(!empty($station['elevation_ft'])), at 420 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 San Diego, CA?
On average, the last spring frost (32°F) around San Diego, CA is about Feb 2. In cooler years it can run later, so for a safer bet many gardeners wait until Dec 31.
When is the first frost in the fall?
The first fall frost around San Diego, CA typically arrives about Dec 7. 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 Feb 2 on average, or Dec 31 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 309 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 92025 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026