Thermal, CA frost dates
Last spring frostFeb 7median date
First fall frostDec 2median date
Growing season298 daysfrost-free
Hardiness zone10aZone 10a
How Thermal compares
- In 8 years out of 10, the last spring frost in Thermal falls between January 7 and March 1, a 53-day window. The first fall frost falls between November 16 and December 21.
- The median last frost is 52 days earlier than the California median of Mar 31.
- Its 298-day growing season is longer than 97% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 23 days earlier than the zone 10a median of Mar 2. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 10a chart.
- The weather station records an average of 19 nights a year at or below 32°F.
- Nearby Indio, CA, 21 km away, gets only light, occasional frost, a reminder of how much elevation and distance from the coast matter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | January 7 |
| 50% (median) | February 7 |
| 10% (safe for tender plants) | March 1 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 16 |
| 50% (median) | December 2 |
| 90% (late) | December 21 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Thermal, CA
Thermal, CA frost dates — last frost Feb 7, first frost Dec 2, zone 10a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Nov 15 to Nov 29Transplant outside: Jan 10 to Jan 24
Start indoors: Nov 29 to Dec 13Transplant outside: Feb 21 to Mar 7
Start indoors: Nov 29 to Dec 13Transplant outside: Feb 21 to Mar 7
Start indoors: Dec 13 to Dec 27Transplant outside: Feb 14 to Feb 28
Start indoors: Dec 13 to Dec 27Transplant outside: Jan 17 to Jan 31Sow outdoors: Jan 10 to Feb 14Plant for fall: Oct 7 to Nov 4
Start indoors: Dec 13 to Dec 27Transplant outside: Jan 10 to Jan 24Sow outdoors: Jan 10 to Jan 24Plant for fall: Sep 23 to Oct 14
Start indoors: Dec 13 to Dec 27Transplant outside: Jan 24 to Feb 7Plant for fall: Aug 26 to Sep 16
Start indoors: Dec 13 to Dec 27Transplant outside: Jan 17 to Jan 31Plant for fall: Aug 26 to Sep 16
Start indoors: Dec 13 to Dec 27Transplant outside: Jan 24 to Feb 7Plant for fall: Aug 26 to Sep 16
Start indoors: Dec 27 to Jan 10Start indoors: Dec 27 to Jan 10Transplant outside: Feb 28 to Mar 14Sow outdoors: Feb 28 to Mar 14
Start indoors: Dec 27 to Jan 10Start indoors: Dec 27 to Jan 10Transplant outside: Feb 14 to Feb 28
Sow outdoors: Dec 27 to Jan 17Sow outdoors: Dec 27 to Jan 17Plant for fall: Sep 9 to Sep 30
Sow outdoors: Dec 27 to Jan 17Sow outdoors: Dec 27 to Jan 17Plant for fall: Oct 7 to Oct 28
Sow outdoors: Jan 3 to Feb 14Plant for fall: Oct 21 to Nov 11
Start indoors: Jan 10 to Jan 17Transplant outside: Feb 21 to Feb 28Sow outdoors: Feb 14 to Feb 28Plant for fall: Sep 16 to Sep 30
Start indoors: Jan 10 to Jan 17Sow outdoors: Feb 14 to Feb 28Plant for fall: Sep 23 to Oct 7
Start indoors: Jan 10 to Jan 17Sow outdoors: Feb 14 to Feb 28
Start indoors: Jan 10 to Jan 17Transplant outside: Feb 21 to Mar 7
Sow outdoors: Jan 17 to Feb 14Plant for fall: Sep 9 to Sep 23
Sow outdoors: Jan 17 to Feb 14Plant for fall: Sep 23 to Oct 7
Sow outdoors: Jan 17 to Feb 7
Sow outdoors: Jan 24 to Feb 21Plant for fall: Sep 23 to Oct 7
Sow outdoors: Jan 24 to Feb 14Plant for fall: Oct 7 to Oct 28
Sow outdoors: Feb 14 to Mar 7Plant for fall: Sep 16 to Sep 30
Sow outdoors: Feb 14 to Feb 28
Transplant outside: Feb 21 to Mar 14
Plant for fall: Nov 18 to Dec 23
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Thermal, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Nov 15 – Nov 29 | Jan 10 – Jan 24 | — | — |
| Peppers | Nov 29 – Dec 13 | Feb 21 – Mar 7 | — | — |
| Eggplant | Nov 29 – Dec 13 | Feb 21 – Mar 7 | — | — |
| Tomatoes | Dec 13 – Dec 27 | Feb 14 – Feb 28 | — | — |
| Lettuce | Dec 13 – Dec 27 | Jan 17 – Jan 31 | Jan 10 – Feb 14 | Oct 7 – Nov 4 |
| Kale | Dec 13 – Dec 27 | Jan 10 – Jan 24 | Jan 10 – Jan 24 | Sep 23 – Oct 14 |
| Broccoli | Dec 13 – Dec 27 | Jan 24 – Feb 7 | — | Aug 26 – Sep 16 |
| Cabbage | Dec 13 – Dec 27 | Jan 17 – Jan 31 | — | Aug 26 – Sep 16 |
| Cauliflower | Dec 13 – Dec 27 | Jan 24 – Feb 7 | — | Aug 26 – Sep 16 |
| Okra | Dec 27 – Jan 10 | Feb 28 – Mar 14 | Feb 28 – Mar 14 | — |
| Basil | Dec 27 – Jan 10 | Feb 14 – Feb 28 | — | — |
| Peas | — | — | Dec 27 – Jan 17 | Sep 9 – Sep 30 |
| Spinach | — | — | Dec 27 – Jan 17 | Oct 7 – Oct 28 |
| Radishes | — | — | Jan 3 – Feb 14 | Oct 21 – Nov 11 |
| Cucumbers | Jan 10 – Jan 17 | Feb 21 – Feb 28 | Feb 14 – Feb 28 | Sep 16 – Sep 30 |
| Zucchini & Summer Squash | Jan 10 – Jan 17 | — | Feb 14 – Feb 28 | Sep 23 – Oct 7 |
| Winter Squash & Pumpkins | Jan 10 – Jan 17 | — | Feb 14 – Feb 28 | — |
| Melons & Watermelon | Jan 10 – Jan 17 | Feb 21 – Mar 7 | — | — |
| Carrots | — | — | Jan 17 – Feb 14 | Sep 9 – Sep 23 |
| Beets | — | — | Jan 17 – Feb 14 | Sep 23 – Oct 7 |
| Potatoes | — | — | Jan 17 – Feb 7 | — |
| Swiss Chard | — | — | Jan 24 – Feb 21 | Sep 23 – Oct 7 |
| Cilantro | — | — | Jan 24 – Feb 14 | Oct 7 – Oct 28 |
| Green Beans | — | — | Feb 14 – Mar 7 | Sep 16 – Sep 30 |
| Sweet Corn | — | — | Feb 14 – Feb 28 | — |
| Sweet Potatoes | — | Feb 21 – Mar 14 | — | — |
| Garlic | — | — | — | Nov 18 – Dec 23 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Desert Resorts Rgnl Ap, CA weather station, 8 km away (elevation -118 ft (-36 m)).
Frost dates near Thermal
- Mecca Jan 6 · Dec 22
- Coachella Dec 31 · Dec 27
- La Quinta Dec 31 · Dec 27
- Indio Dec 31 · Dec 27
- Indian Wells Dec 31 · Dec 27
- Palm Desert Dec 31 · Dec 27
- Salton City Jan 7 · Jan 4
- Rancho Mirage Jan 9 · Jan 9
- Thousand Palms Jan 9 · Jan 9
- Cathedral City Jan 9 · Jan 9
Frequently asked questions
When is the last frost in Thermal, CA?
The median last spring frost in Thermal, CA is February 7. There is still about a 10% chance of frost after March 1, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Thermal, CA?
The median first fall frost is December 2, with about a 10% chance of frost before November 16.
How long is the growing season in Thermal, CA?
About 298 days between the median last spring frost and first fall frost.
What planting zone is Thermal, CA?
Thermal, CA is in USDA hardiness zone 10a.