Callahan, CA frost dates
Last spring frostMay 20median date
First fall frostOct 5median date
Growing season138 daysfrost-free
Hardiness zone8aZone 8a
How Callahan compares
- In 8 years out of 10, the last spring frost in Callahan falls between May 2 and June 12, a 41-day window. The first fall frost falls between September 20 and October 22.
- The median last frost is 50 days later than the California median of Mar 31.
- Its 138-day growing season is longer than 11% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 52 days later than the zone 8a median of Mar 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 8a chart.
- The weather station records an average of 148 nights a year at or below 32°F.
- Nearby Redding, CA, 90 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) | May 2 |
| 50% (median) | May 20 |
| 10% (safe for tender plants) | June 12 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 20 |
| 50% (median) | October 5 |
| 90% (late) | October 22 |
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 Callahan, CA
Callahan, CA frost dates — last frost May 20, first frost Oct 5, zone 8a. whenisthelastfrost.com
Crop
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Start indoors: Feb 25 to Mar 11Transplant outside: Apr 22 to May 6
Start indoors: Mar 11 to Mar 25Transplant outside: Jun 3 to Jun 17
Start indoors: Mar 11 to Mar 25Transplant outside: Jun 3 to Jun 17
Start indoors: Mar 25 to Apr 8Transplant outside: May 27 to Jun 10
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 29 to May 13Sow outdoors: Apr 22 to May 27Plant for fall: Aug 10 to Sep 7
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 22 to May 6Sow outdoors: Apr 22 to May 6Plant for fall: Jul 27 to Aug 17
Start indoors: Mar 25 to Apr 8Transplant outside: May 6 to May 20Plant for fall: Jun 29 to Jul 20
Start indoors: Mar 25 to Apr 8Transplant outside: Apr 29 to May 13Plant for fall: Jun 29 to Jul 20
Start indoors: Mar 25 to Apr 8Transplant outside: May 6 to May 20Plant for fall: Jun 29 to Jul 20
Start indoors: Apr 8 to Apr 22Transplant outside: Jun 10 to Jun 24Sow outdoors: Jun 10 to Jun 24
Start indoors: Apr 8 to Apr 22Transplant outside: May 27 to Jun 10
Sow outdoors: Apr 8 to Apr 29Plant for fall: Jul 13 to Aug 3
Sow outdoors: Apr 8 to Apr 29Plant for fall: Aug 10 to Aug 31
Sow outdoors: Apr 15 to May 27Plant for fall: Aug 24 to Sep 14
Start indoors: Apr 22 to Apr 29Transplant outside: Jun 3 to Jun 10Sow outdoors: May 27 to Jun 10Plant for fall: Jul 20 to Aug 3
Start indoors: Apr 22 to Apr 29Sow outdoors: May 27 to Jun 10Plant for fall: Jul 27 to Aug 10
Start indoors: Apr 22 to Apr 29Sow outdoors: May 27 to Jun 10
Start indoors: Apr 22 to Apr 29Transplant outside: Jun 3 to Jun 17
Sow outdoors: Apr 29 to May 27Plant for fall: Jul 13 to Jul 27
Sow outdoors: Apr 29 to May 27Plant for fall: Jul 27 to Aug 10
Sow outdoors: Apr 29 to May 20
Sow outdoors: May 6 to Jun 3Plant for fall: Jul 27 to Aug 10
Sow outdoors: May 6 to May 27Plant for fall: Aug 10 to Aug 31
Sow outdoors: May 27 to Jun 17Plant for fall: Jul 20 to Aug 3
Sow outdoors: May 27 to Jun 10
Transplant outside: Jun 3 to Jun 24
Plant for fall: Sep 21 to Oct 26
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Callahan, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 25 – Mar 11 | Apr 22 – May 6 | — | — |
| Peppers | Mar 11 – Mar 25 | Jun 3 – Jun 17 | — | — |
| Eggplant | Mar 11 – Mar 25 | Jun 3 – Jun 17 | — | — |
| Tomatoes | Mar 25 – Apr 8 | May 27 – Jun 10 | — | — |
| Lettuce | Mar 25 – Apr 8 | Apr 29 – May 13 | Apr 22 – May 27 | Aug 10 – Sep 7 |
| Kale | Mar 25 – Apr 8 | Apr 22 – May 6 | Apr 22 – May 6 | Jul 27 – Aug 17 |
| Broccoli | Mar 25 – Apr 8 | May 6 – May 20 | — | Jun 29 – Jul 20 |
| Cabbage | Mar 25 – Apr 8 | Apr 29 – May 13 | — | Jun 29 – Jul 20 |
| Cauliflower | Mar 25 – Apr 8 | May 6 – May 20 | — | Jun 29 – Jul 20 |
| Okra | Apr 8 – Apr 22 | Jun 10 – Jun 24 | Jun 10 – Jun 24 | — |
| Basil | Apr 8 – Apr 22 | May 27 – Jun 10 | — | — |
| Peas | — | — | Apr 8 – Apr 29 | Jul 13 – Aug 3 |
| Spinach | — | — | Apr 8 – Apr 29 | Aug 10 – Aug 31 |
| Radishes | — | — | Apr 15 – May 27 | Aug 24 – Sep 14 |
| Cucumbers | Apr 22 – Apr 29 | Jun 3 – Jun 10 | May 27 – Jun 10 | Jul 20 – Aug 3 |
| Zucchini & Summer Squash | Apr 22 – Apr 29 | — | May 27 – Jun 10 | Jul 27 – Aug 10 |
| Winter Squash & Pumpkins | Apr 22 – Apr 29 | — | May 27 – Jun 10 | — |
| Melons & Watermelon | Apr 22 – Apr 29 | Jun 3 – Jun 17 | — | — |
| Carrots | — | — | Apr 29 – May 27 | Jul 13 – Jul 27 |
| Beets | — | — | Apr 29 – May 27 | Jul 27 – Aug 10 |
| Potatoes | — | — | Apr 29 – May 20 | — |
| Swiss Chard | — | — | May 6 – Jun 3 | Jul 27 – Aug 10 |
| Cilantro | — | — | May 6 – May 27 | Aug 10 – Aug 31 |
| Green Beans | — | — | May 27 – Jun 17 | Jul 20 – Aug 3 |
| Sweet Corn | — | — | May 27 – Jun 10 | — |
| Sweet Potatoes | — | Jun 3 – Jun 24 | — | — |
| Garlic | — | — | — | Sep 21 – Oct 26 |
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 Callahan, CA weather station, 7 km away (elevation 3,084 ft (940 m)).
Frost dates near Callahan
- Etna May 20 · Oct 5
- Greenview May 20 · Oct 5
- Gazelle Apr 30 · Oct 18
- Fort Jones Apr 30 · Oct 18
- Weed May 6 · Oct 12
- Grenada Apr 30 · Oct 18
- Trinity Center May 20 · Oct 5
- Mount Shasta May 15 · Oct 6
- Yreka Apr 30 · Oct 18
- Forks Of Salmon Apr 27 · Oct 21
Frequently asked questions
When is the last frost in Callahan, CA?
The median last spring frost in Callahan, CA is May 20. There is still about a 10% chance of frost after June 12, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Callahan, CA?
The median first fall frost is October 5, with about a 10% chance of frost before September 20.
How long is the growing season in Callahan, CA?
About 138 days between the median last spring frost and first fall frost.
What planting zone is Callahan, CA?
Callahan, CA is in USDA hardiness zone 8a.