Last spring frost
Mar 19
Frost Dates for Eucalyptus Hills, CA
First fall frost
Dec 8
Growing season
270 days
Hardiness zone
10a
In an average year around Eucalyptus Hills, CA, the last spring frost (32°F) is about Mar 19 and the first fall frost is about Dec 8, giving roughly a 270-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) | Jun 29 | Apr 24 | Feb 23 |
| Freeze (32°F) | Jun 1 | Mar 19 | Dec 31 |
| Hard (28°F) | Apr 20 | Feb 22 | Dec 20 |
| Severe (24°F) | Mar 28 | Feb 4 | Dec 27 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 29 | Jun 14 | May 29 | May 5 | Apr 24 | Apr 13 | Mar 31 | Mar 14 | Feb 23 |
| 32°F | Jun 1 | May 3 | Apr 14 | Mar 31 | Mar 19 | Feb 28 | Feb 19 | Jan 29 | Dec 31 |
| 28°F | Apr 20 | Mar 29 | Mar 13 | Feb 28 | Feb 22 | Feb 12 | Jan 31 | Jan 14 | Dec 20 |
| 24°F | Mar 28 | Feb 28 | Feb 22 | Feb 14 | Feb 4 | Jan 30 | Jan 20 | Jan 11 | Dec 27 |
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 16 | Nov 19 | Dec 13 |
| Freeze (32°F) | Oct 25 | Dec 8 | Jan 15 |
| Hard (28°F) | Nov 26 | Jan 1 | Feb 25 |
| Severe (24°F) | Dec 6 | Jan 18 | Mar 1 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 16 | Oct 7 | Oct 28 | Nov 9 | Nov 19 | Nov 25 | Nov 30 | Dec 4 | Dec 13 |
| 32°F | Oct 25 | Nov 16 | Nov 28 | Dec 1 | Dec 8 | Dec 14 | Dec 21 | Dec 30 | Jan 15 |
| 28°F | Nov 26 | Dec 4 | Dec 14 | Dec 26 | Jan 1 | Jan 8 | Jan 22 | Feb 5 | Feb 25 |
| 24°F | Dec 6 | Dec 31 | Jan 5 | Jan 11 | Jan 18 | Jan 26 | Feb 3 | Feb 17 | Mar 1 |
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: El Capitan Dam, Ca, about 4.7 miles away@if(!empty($station['elevation_ft'])), at 600 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 Eucalyptus Hills, CA?
On average, the last spring frost (32°F) around Eucalyptus Hills, CA is about Mar 19. 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 Eucalyptus Hills, CA typically arrives about Dec 8. 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 19 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 270 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 92040 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026