Amboy, CA frost dates
Last spring frostMar 6median date
First fall frostDec 8median date
Growing season277 daysfrost-free
Hardiness zone9bZone 9b
How Amboy compares
- In 8 years out of 10, the last spring frost in Amboy falls between January 17 and April 9, a 82-day window. The first fall frost falls between November 12 and January 5.
- The median last frost is 25 days earlier than the California median of Mar 31.
- Its 277-day growing season is longer than 78% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 14 days later than the zone 9b median of Feb 20. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 9b chart.
- The weather station records an average of 22 nights a year at or below 32°F.
- Nearby Indio, CA, 99 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 17 |
| 50% (median) | March 6 |
| 10% (safe for tender plants) | April 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 12 |
| 50% (median) | December 8 |
| 90% (late) | January 5 |
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 Amboy, CA
Amboy, CA frost dates — last frost Mar 6, first frost Dec 8, zone 9b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Dec 12 to Dec 26Transplant outside: Feb 6 to Feb 20
Start indoors: Dec 26 to Jan 9Start indoors: Dec 26 to Jan 9Transplant outside: Mar 20 to Apr 3
Start indoors: Dec 26 to Jan 9Start indoors: Dec 26 to Jan 9Transplant outside: Mar 20 to Apr 3
Start indoors: Jan 9 to Jan 23Transplant outside: Mar 13 to Mar 27
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 13 to Feb 27Sow outdoors: Feb 6 to Mar 13Plant for fall: Oct 13 to Nov 10
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 6 to Feb 20Sow outdoors: Feb 6 to Feb 20Plant for fall: Sep 29 to Oct 20
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 20 to Mar 6Plant for fall: Sep 1 to Sep 22
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 13 to Feb 27Plant for fall: Sep 1 to Sep 22
Start indoors: Jan 9 to Jan 23Transplant outside: Feb 20 to Mar 6Plant for fall: Sep 1 to Sep 22
Start indoors: Jan 23 to Feb 6Transplant outside: Mar 27 to Apr 10Sow outdoors: Mar 27 to Apr 10
Start indoors: Jan 23 to Feb 6Transplant outside: Mar 13 to Mar 27
Sow outdoors: Jan 23 to Feb 13Plant for fall: Sep 15 to Oct 6
Sow outdoors: Jan 23 to Feb 13Plant for fall: Oct 13 to Nov 3
Sow outdoors: Jan 30 to Mar 13Plant for fall: Oct 27 to Nov 17
Start indoors: Feb 6 to Feb 13Transplant outside: Mar 20 to Mar 27Sow outdoors: Mar 13 to Mar 27Plant for fall: Sep 22 to Oct 6
Start indoors: Feb 6 to Feb 13Sow outdoors: Mar 13 to Mar 27Plant for fall: Sep 29 to Oct 13
Start indoors: Feb 6 to Feb 13Sow outdoors: Mar 13 to Mar 27
Start indoors: Feb 6 to Feb 13Transplant outside: Mar 20 to Apr 3
Sow outdoors: Feb 13 to Mar 13Plant for fall: Sep 15 to Sep 29
Sow outdoors: Feb 13 to Mar 13Plant for fall: Sep 29 to Oct 13
Sow outdoors: Feb 13 to Mar 6
Sow outdoors: Feb 20 to Mar 20Plant for fall: Sep 29 to Oct 13
Sow outdoors: Feb 20 to Mar 13Plant for fall: Oct 13 to Nov 3
Sow outdoors: Mar 13 to Apr 3Plant for fall: Sep 22 to Oct 6
Sow outdoors: Mar 13 to Mar 27
Transplant outside: Mar 20 to Apr 10
Plant for fall: Nov 24 to Dec 29
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Amboy, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Dec 12 – Dec 26 | Feb 6 – Feb 20 | — | — |
| Peppers | Dec 26 – Jan 9 | Mar 20 – Apr 3 | — | — |
| Eggplant | Dec 26 – Jan 9 | Mar 20 – Apr 3 | — | — |
| Tomatoes | Jan 9 – Jan 23 | Mar 13 – Mar 27 | — | — |
| Lettuce | Jan 9 – Jan 23 | Feb 13 – Feb 27 | Feb 6 – Mar 13 | Oct 13 – Nov 10 |
| Kale | Jan 9 – Jan 23 | Feb 6 – Feb 20 | Feb 6 – Feb 20 | Sep 29 – Oct 20 |
| Broccoli | Jan 9 – Jan 23 | Feb 20 – Mar 6 | — | Sep 1 – Sep 22 |
| Cabbage | Jan 9 – Jan 23 | Feb 13 – Feb 27 | — | Sep 1 – Sep 22 |
| Cauliflower | Jan 9 – Jan 23 | Feb 20 – Mar 6 | — | Sep 1 – Sep 22 |
| Okra | Jan 23 – Feb 6 | Mar 27 – Apr 10 | Mar 27 – Apr 10 | — |
| Basil | Jan 23 – Feb 6 | Mar 13 – Mar 27 | — | — |
| Peas | — | — | Jan 23 – Feb 13 | Sep 15 – Oct 6 |
| Spinach | — | — | Jan 23 – Feb 13 | Oct 13 – Nov 3 |
| Radishes | — | — | Jan 30 – Mar 13 | Oct 27 – Nov 17 |
| Cucumbers | Feb 6 – Feb 13 | Mar 20 – Mar 27 | Mar 13 – Mar 27 | Sep 22 – Oct 6 |
| Zucchini & Summer Squash | Feb 6 – Feb 13 | — | Mar 13 – Mar 27 | Sep 29 – Oct 13 |
| Winter Squash & Pumpkins | Feb 6 – Feb 13 | — | Mar 13 – Mar 27 | — |
| Melons & Watermelon | Feb 6 – Feb 13 | Mar 20 – Apr 3 | — | — |
| Carrots | — | — | Feb 13 – Mar 13 | Sep 15 – Sep 29 |
| Beets | — | — | Feb 13 – Mar 13 | Sep 29 – Oct 13 |
| Potatoes | — | — | Feb 13 – Mar 6 | — |
| Swiss Chard | — | — | Feb 20 – Mar 20 | Sep 29 – Oct 13 |
| Cilantro | — | — | Feb 20 – Mar 13 | Oct 13 – Nov 3 |
| Green Beans | — | — | Mar 13 – Apr 3 | Sep 22 – Oct 6 |
| Sweet Corn | — | — | Mar 13 – Mar 27 | — |
| Sweet Potatoes | — | Mar 20 – Apr 10 | — | — |
| Garlic | — | — | — | Nov 24 – Dec 29 |
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 Mitchell Caverns, CA weather station, 47 km away (elevation 4,350 ft (1,326 m)). That is far enough away that your dates may differ, especially if your elevation is different.
Frost dates near Amboy
- Essex Mar 6 · Dec 8
- Ludlow Mar 1 · Nov 29
- Twentynine Palms Jan 24 · Dec 10
- Joshua Tree Feb 28 · Dec 1
- Yucca Valley Mar 14 · Nov 28
- Landers Mar 1 · Nov 29
- Cima Mar 6 · Dec 8
- Pioneertown Feb 16 · Dec 10
- Desert Center Jan 10 · Jan 8
- Morongo Valley Feb 25 · Dec 15
Frequently asked questions
When is the last frost in Amboy, CA?
The median last spring frost in Amboy, CA is March 6. There is still about a 10% chance of frost after April 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Amboy, CA?
The median first fall frost is December 8, with about a 10% chance of frost before November 12.
How long is the growing season in Amboy, CA?
About 277 days between the median last spring frost and first fall frost.
What planting zone is Amboy, CA?
Amboy, CA is in USDA hardiness zone 9b.