Julian, CA frost dates
Last spring frostMar 27median date
First fall frostDec 1median date
Growing season249 daysfrost-free
Hardiness zone9bZone 9b
How Julian compares
- In 8 years out of 10, the last spring frost in Julian falls between February 17 and April 30, a 72-day window. The first fall frost falls between November 3 and December 21.
- The median last frost is 4 days earlier than the California median of Mar 31.
- Its 249-day growing season is longer than 55% of the 636 California places with a regular frost season (state median 235 days).
- The last frost is 35 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 37 nights a year at or below 32°F.
- Nearby Poway, CA, 45 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) | February 17 |
| 50% (median) | March 27 |
| 10% (safe for tender plants) | April 30 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 3 |
| 50% (median) | December 1 |
| 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 Julian, CA
Julian, CA frost dates — last frost Mar 27, first frost Dec 1, zone 9b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Jan 2 to Jan 16Transplant outside: Feb 27 to Mar 13
Start indoors: Jan 16 to Jan 30Transplant outside: Apr 10 to Apr 24
Start indoors: Jan 16 to Jan 30Transplant outside: Apr 10 to Apr 24
Start indoors: Jan 30 to Feb 13Transplant outside: Apr 3 to Apr 17
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 6 to Mar 20Sow outdoors: Feb 27 to Apr 3Plant for fall: Oct 6 to Nov 3
Start indoors: Jan 30 to Feb 13Transplant outside: Feb 27 to Mar 13Sow outdoors: Feb 27 to Mar 13Plant for fall: Sep 22 to Oct 13
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 13 to Mar 27Plant for fall: Aug 25 to Sep 15
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 6 to Mar 20Plant for fall: Aug 25 to Sep 15
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 13 to Mar 27Plant for fall: Aug 25 to Sep 15
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 17 to May 1Sow outdoors: Apr 17 to May 1
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 3 to Apr 17
Sow outdoors: Feb 13 to Mar 6Plant for fall: Sep 8 to Sep 29
Sow outdoors: Feb 13 to Mar 6Plant for fall: Oct 6 to Oct 27
Sow outdoors: Feb 20 to Apr 3Plant for fall: Oct 20 to Nov 10
Start indoors: Feb 27 to Mar 6Transplant outside: Apr 10 to Apr 17Sow outdoors: Apr 3 to Apr 17Plant for fall: Sep 15 to Sep 29
Start indoors: Feb 27 to Mar 6Sow outdoors: Apr 3 to Apr 17Plant for fall: Sep 22 to Oct 6
Start indoors: Feb 27 to Mar 6Sow outdoors: Apr 3 to Apr 17
Start indoors: Feb 27 to Mar 6Transplant outside: Apr 10 to Apr 24
Sow outdoors: Mar 6 to Apr 3Plant for fall: Sep 8 to Sep 22
Sow outdoors: Mar 6 to Apr 3Plant for fall: Sep 22 to Oct 6
Sow outdoors: Mar 6 to Mar 27
Sow outdoors: Mar 13 to Apr 10Plant for fall: Sep 22 to Oct 6
Sow outdoors: Mar 13 to Apr 3Plant for fall: Oct 6 to Oct 27
Sow outdoors: Apr 3 to Apr 24Plant for fall: Sep 15 to Sep 29
Sow outdoors: Apr 3 to Apr 17
Transplant outside: Apr 10 to May 1
Plant for fall: Nov 17 to Dec 22
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Julian, CA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 2 – Jan 16 | Feb 27 – Mar 13 | — | — |
| Peppers | Jan 16 – Jan 30 | Apr 10 – Apr 24 | — | — |
| Eggplant | Jan 16 – Jan 30 | Apr 10 – Apr 24 | — | — |
| Tomatoes | Jan 30 – Feb 13 | Apr 3 – Apr 17 | — | — |
| Lettuce | Jan 30 – Feb 13 | Mar 6 – Mar 20 | Feb 27 – Apr 3 | Oct 6 – Nov 3 |
| Kale | Jan 30 – Feb 13 | Feb 27 – Mar 13 | Feb 27 – Mar 13 | Sep 22 – Oct 13 |
| Broccoli | Jan 30 – Feb 13 | Mar 13 – Mar 27 | — | Aug 25 – Sep 15 |
| Cabbage | Jan 30 – Feb 13 | Mar 6 – Mar 20 | — | Aug 25 – Sep 15 |
| Cauliflower | Jan 30 – Feb 13 | Mar 13 – Mar 27 | — | Aug 25 – Sep 15 |
| Okra | Feb 13 – Feb 27 | Apr 17 – May 1 | Apr 17 – May 1 | — |
| Basil | Feb 13 – Feb 27 | Apr 3 – Apr 17 | — | — |
| Peas | — | — | Feb 13 – Mar 6 | Sep 8 – Sep 29 |
| Spinach | — | — | Feb 13 – Mar 6 | Oct 6 – Oct 27 |
| Radishes | — | — | Feb 20 – Apr 3 | Oct 20 – Nov 10 |
| Cucumbers | Feb 27 – Mar 6 | Apr 10 – Apr 17 | Apr 3 – Apr 17 | Sep 15 – Sep 29 |
| Zucchini & Summer Squash | Feb 27 – Mar 6 | — | Apr 3 – Apr 17 | Sep 22 – Oct 6 |
| Winter Squash & Pumpkins | Feb 27 – Mar 6 | — | Apr 3 – Apr 17 | — |
| Melons & Watermelon | Feb 27 – Mar 6 | Apr 10 – Apr 24 | — | — |
| Carrots | — | — | Mar 6 – Apr 3 | Sep 8 – Sep 22 |
| Beets | — | — | Mar 6 – Apr 3 | Sep 22 – Oct 6 |
| Potatoes | — | — | Mar 6 – Mar 27 | — |
| Swiss Chard | — | — | Mar 13 – Apr 10 | Sep 22 – Oct 6 |
| Cilantro | — | — | Mar 13 – Apr 3 | Oct 6 – Oct 27 |
| Green Beans | — | — | Apr 3 – Apr 24 | Sep 15 – Sep 29 |
| Sweet Corn | — | — | Apr 3 – Apr 17 | — |
| Sweet Potatoes | — | Apr 10 – May 1 | — | — |
| Garlic | — | — | — | Nov 17 – Dec 22 |
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 Julian Cdf, CA weather station, 4 km away (elevation 4,216 ft (1,285 m)).
Frost dates near Julian
- Santa Ysabel Apr 18 · Oct 26
- Ranchita Jan 10 · Jan 1
- Descanso Apr 19 · Oct 27
- San Ysidro Jan 10 · Jan 1
- Guatay Apr 22 · Nov 8
- Mount Laguna Apr 22 · Nov 8
- Pine Valley Apr 22 · Nov 8
- Ramona Mar 4 · Dec 4
- Borrego Springs Jan 10 · Jan 1
- Warner Springs Apr 18 · Oct 26
Frequently asked questions
When is the last frost in Julian, CA?
The median last spring frost in Julian, CA is March 27. There is still about a 10% chance of frost after April 30, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Julian, CA?
The median first fall frost is December 1, with about a 10% chance of frost before November 3.
How long is the growing season in Julian, CA?
About 249 days between the median last spring frost and first fall frost.
What planting zone is Julian, CA?
Julian, CA is in USDA hardiness zone 9b.