When to plant in Fairfield, CA
USDA Zone 9bFairfield, California frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Fairfield enjoys a long ~333-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. In zone 9b, frost is a minor factor for Fairfield — most perennials thrive, and annual vegetables can go out early and stay late.
The average last spring frost in Fairfield is now 13 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
FAIRFIELD · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Fairfield’s own odds, recorded at FAIRFIELD.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 4 | Feb 25 | Jan 23 | Nov 13 | Dec 1 | Dec 21 |
| 32°F | Feb 16 | Jan 15 | Dec 22 | Nov 29 | Dec 14 | Jan 9 |
| 28°F | Jan 19 | Dec 31 | Dec 13 | Dec 6 | Dec 24 | Jan 11 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.
Full-year planting calendar
Each bar is the exact window to take a planting action in Fairfield, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 16 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Fairfield planting FAQ
When is the last spring frost in Fairfield, CA?
On average, the last spring frost in Fairfield is around January 15 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Fairfield, CA?
In Fairfield, the first 32°F freeze of fall lands around December 14 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Fairfield in?
Fairfield is in USDA hardiness zone 9b. In zone 9b, winters are mild — many tender perennials overwinter here.
How long is the growing season in Fairfield?
Fairfield has about 333 frost-free days — a long growing season — between the average last spring frost (January 15) and first fall frost (December 14).
When should I plant tomatoes in Fairfield?
For Fairfield, sow tomatoes indoors about November 20–December 4 and move the seedlings out around January 22, after the last spring frost.
Never miss a window in Fairfield
An email when it’s time to start seeds, transplant, and sow — timed to Fairfield’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Suisun City · 2 km
- Vacaville · 12 km
- American Canyon · 22 km
- Benicia · 24 km
- Napa · 24 km
- Bay Point · 26 km
- Vallejo · 26 km
- Dixon · 27 km
Frost dates recorded at FAIRFIELD, 3 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Fairfield, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00042934. Retrieved from https://blissgarden.com/california/fairfield.