Last spring frost
Mar 4
Frost Dates for Ramona, CA
First fall frost
Dec 4
Growing season
270 days
Hardiness zone
9b
In an average year around Ramona, CA, the last spring frost (32°F) is about Mar 4 and the first fall frost is about Dec 4, giving roughly a 270-day growing season. To be safe most years, wait until Jan 29 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 28 | Apr 10 | Mar 17 |
| Freeze (32°F) | Apr 10 | Mar 4 | Jan 29 |
| Hard (28°F) | Mar 1 | Jan 31 | Dec 23 |
| Severe (24°F) | Feb 19 | Jan 11 | Dec 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 28 | Apr 21 | Apr 17 | Apr 13 | Apr 10 | Apr 6 | Apr 3 | Mar 30 | Mar 17 |
| 32°F | Apr 10 | Mar 31 | Mar 23 | Mar 11 | Mar 4 | Feb 27 | Feb 21 | Feb 13 | Jan 29 |
| 28°F | Mar 1 | Feb 23 | Feb 15 | Feb 8 | Jan 31 | Jan 20 | Jan 11 | Dec 31 | Dec 23 |
| 24°F | Feb 19 | Feb 9 | Jan 31 | Jan 20 | Jan 11 | Jan 5 | Dec 31 | Dec 26 | Dec 16 |
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 26 | Nov 19 | Dec 4 |
| Freeze (32°F) | Nov 17 | Dec 4 | Dec 18 |
| Hard (28°F) | Dec 1 | Dec 19 | Jan 16 |
| Severe (24°F) | Dec 12 | Jan 3 | Feb 13 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 26 | Nov 3 | Nov 9 | Nov 14 | Nov 19 | Nov 22 | Nov 26 | Dec 1 | Dec 4 |
| 32°F | Nov 17 | Nov 25 | Nov 30 | Dec 2 | Dec 4 | Dec 7 | Dec 11 | Dec 14 | Dec 18 |
| 28°F | Dec 1 | Dec 8 | Dec 12 | Dec 16 | Dec 19 | Dec 23 | Dec 27 | Jan 2 | Jan 16 |
| 24°F | Dec 12 | Dec 20 | Dec 26 | Dec 30 | Jan 3 | Jan 8 | Jan 15 | Jan 31 | Feb 13 |
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: Ramona Fire Dept, Ca, about 4.9 miles away@if(!empty($station['elevation_ft'])), at 1,470 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 Ramona, CA?
On average, the last spring frost (32°F) around Ramona, CA is about Mar 4. In cooler years it can run later, so for a safer bet many gardeners wait until Jan 29.
When is the first frost in the fall?
The first fall frost around Ramona, CA typically arrives about Dec 4. 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 4 on average, or Jan 29 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 92065 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026