Last spring frost
Feb 28
Frost Dates for Joshua Tree, CA
First fall frost
Dec 1
Growing season
273 days
Hardiness zone
9a
In an average year around Joshua Tree, CA, the last spring frost (32°F) is about Feb 28 and the first fall frost is about Dec 1, giving roughly a 273-day growing season. To be safe most years, wait until Jan 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%) |
|---|---|---|---|
| Light (36°F) | Apr 18 | Mar 30 | Mar 1 |
| Freeze (32°F) | Mar 28 | Feb 28 | Jan 21 |
| Hard (28°F) | Feb 28 | Jan 24 | Dec 22 |
| Severe (24°F) | Feb 16 | Jan 5 | Dec 13 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 18 | Apr 11 | Apr 7 | Apr 3 | Mar 30 | Mar 24 | Mar 18 | Mar 13 | Mar 1 |
| 32°F | Mar 28 | Mar 19 | Mar 11 | Mar 5 | Feb 28 | Feb 22 | Feb 15 | Feb 4 | Jan 21 |
| 28°F | Feb 28 | Feb 20 | Feb 11 | Feb 3 | Jan 24 | Jan 14 | Jan 6 | Jan 1 | Dec 22 |
| 24°F | Feb 16 | Feb 6 | Jan 24 | Jan 11 | Jan 5 | Jan 1 | Dec 30 | Dec 21 | Dec 13 |
| 20°F | Feb 12 | Jan 13 | Jan 6 | Jan 2 | Dec 31 | Dec 29 | Dec 27 | Dec 23 | Dec 18 |
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 28 | Nov 16 | Dec 2 |
| Freeze (32°F) | Nov 12 | Dec 1 | Dec 17 |
| Hard (28°F) | Nov 28 | Dec 15 | Jan 7 |
| Severe (24°F) | Dec 9 | Dec 29 | Feb 6 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 28 | Nov 3 | Nov 8 | Nov 13 | Nov 16 | Nov 20 | Nov 23 | Nov 27 | Dec 2 |
| 32°F | Nov 12 | Nov 20 | Nov 24 | Nov 28 | Dec 1 | Dec 5 | Dec 8 | Dec 12 | Dec 17 |
| 28°F | Nov 28 | Dec 4 | Dec 8 | Dec 12 | Dec 15 | Dec 19 | Dec 23 | Dec 28 | Jan 7 |
| 24°F | Dec 9 | Dec 14 | Dec 19 | Dec 25 | Dec 29 | Jan 1 | Jan 6 | Jan 17 | Feb 6 |
| 20°F | Dec 15 | Dec 21 | Dec 24 | Dec 28 | Dec 30 | Jan 1 | Jan 4 | Jan 11 | Feb 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: Joshua Tree, Ca, about 0.5 miles away@if(!empty($station['elevation_ft'])), at 2,563 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 Joshua Tree, CA?
On average, the last spring frost (32°F) around Joshua Tree, CA is about Feb 28. In cooler years it can run later, so for a safer bet many gardeners wait until Jan 21.
When is the first frost in the fall?
The first fall frost around Joshua Tree, CA typically arrives about Dec 1. 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 28 on average, or Jan 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 273 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 92252 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026