Fairfield, CA planting zone & frost dates

Fairfield is in USDA hardiness zone 9b. The last spring frost usually comes around January 15 and the first fall frost around December 14, for a growing season of about 336 days.

USDA hardiness zone9bavg. extreme winter low 25°F to 30°F

Average last spring frostJanuary 1590% chance of no frost after February 16

Average first fall frostDecember 1410% chance of frost by November 29

Growing season336 daysfrost-free days in an average year

Planting calendar for Fairfield

Dates are counted from the average last spring frost (January 15) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.

Crop	When
Tomatoes	Start seeds indoors: Nov 20 – Dec 4 Transplant outdoors: Jan 22 – Jan 29
Peppers	Start seeds indoors: Nov 6 – Nov 20 Transplant outdoors: Jan 29 – Feb 5
Eggplant	Start seeds indoors: Nov 6 – Nov 20 Transplant outdoors: Jan 29 – Feb 5
Broccoli	Start seeds indoors: Nov 6 – Nov 20 Transplant outdoors: Dec 18 – Jan 1
Cabbage	Start seeds indoors: Nov 6 – Nov 20 Transplant outdoors: Dec 18 – Jan 1
Onions (sets)	Plant outdoors: Dec 18 – Jan 1
Peas	Sow outdoors: Dec 4 – Dec 18
Spinach	Sow outdoors: Dec 4 – Dec 18
Lettuce	Sow outdoors: Dec 18 – Jan 1
Carrots	Sow outdoors: Dec 18 – Jan 1
Potatoes	Plant outdoors: Dec 18 – Jan 1
Beans	Sow outdoors: Jan 22 – Jan 29
Sweet corn	Sow outdoors: Jan 22 – Jan 29
Cucumbers	Sow outdoors: Jan 22 – Jan 29
Squash & zucchini	Sow outdoors: Jan 22 – Jan 29
Basil	Start seeds indoors: Dec 4 – Dec 18 Transplant outdoors: Jan 22 – Jan 29

Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 19 (8 weeks before the average first fall frost on Dec 14).

Frost risk in detail

	90% chance	50% chance	10% chance
Last 32°F frost in spring is after	Dec 22	Jan 15	Feb 16
First 32°F frost in fall is before	Jan 9	Dec 14	Nov 29

How to read it: in spring there is a 10% chance of a frost after February 16, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 29. A hard freeze (28°F) usually ends around December 31.

Hardiness zone by ZIP code in Fairfield

94533 zone 9b
94534 zone 9b

Nearby cities

Suisun zone 9b, last frost Jan 15
Vacaville zone 9b, last frost Feb 18
Benicia zone 9b, last frost Feb 28
American Canyon zone 9b, last frost Mar 5
Bay Point zone 9b, last frost Jan 9
Martinez zone 9b, last frost Feb 28
Napa zone 9b, last frost Feb 12
Vallejo zone 9b, last frost Jan 17

All cities in California → · Other zone 9b cities →

Questions

What growing zone is Fairfield, CA?

Fairfield is in USDA Plant Hardiness Zone 9b (average extreme winter low 25°F to 30°F), according to the USDA 2023 map.

When is the last frost in Fairfield?

The average last spring frost (32°F) in Fairfield is January 15. There is still a 10% chance of frost until February 16.

When can I plant tomatoes in Fairfield?

Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Jan 22 – Jan 29. Start seeds indoors 6–8 weeks before the last frost.

Frost dates: NOAA U.S. Climate Normals 1991–2020, station Fairfield, CA (USC00042934), 3.6 km (2.2 mi) from the city center, elevation 12 m, based on 27 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.