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When to plant in Benicia, CA

USDA Zone 9b

Benicia, California frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

With about 344 frost-free days, Benicia supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. In zone 9b, frost is a minor factor for Benicia — most perennials thrive, and annual vegetables can go out early and stay late.

Station · VALLEJO · 4.1 km
Last spring frost
January 17
50% chance · 32°F
First fall frost
December 27
50% chance · 32°F
Growing season
344 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for BeniciaA year-band showing 32°F frost risk from January to December for Benicia: last spring frost around January 17, first fall frost around December 27, about 344 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

VALLEJO · 1991–2020

The 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 Benicia’s own odds, recorded at VALLEJO.

Frost-probability curves for BeniciaProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 17 and the first fall frost around December 27, giving about 344 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FApr 8Mar 4Jan 19Nov 21Dec 7Jan 2
32°FMar 4Jan 17Dec 23Dec 4Dec 27Feb 4
28°FJan 19Jan 5Dec 19Dec 13Jan 2Jan 19

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19

Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.

Add the next planting windows to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Benicia, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 12 km · complete 32°F normals

When 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.

VALLEJO
Primary
4 km · 104 m elevation
SPRING
Jan 17
FALL
Dec 27
MARTINEZ WTP
8 km · 12 m elevation
SPRING
Feb 28
FALL
Nov 22
CONCORD WWTP
12 km · 12 m elevation
SPRING
Jan 7
FALL
Dec 19

Benicia planting FAQ

When is the last spring frost in Benicia, CA?

Benicia's average last spring frost falls near January 17 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in Benicia, CA?

Expect Benicia's first fall frost near December 27 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Benicia in?

Benicia is in USDA hardiness zone 9b. In zone 9b, winters are mild — many tender perennials overwinter here.

How long is the growing season in Benicia?

Benicia has about 344 frost-free days — a long growing season — between the average last spring frost (January 17) and first fall frost (December 27).

When should I plant tomatoes in Benicia?

For Benicia, sow tomatoes indoors about November 22–December 6 and move the seedlings out around January 24, after the last spring frost.

Planting reminders

Never miss a window in Benicia

An email when it’s time to start seeds, transplant, and sow — timed to Benicia’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at VALLEJO, 4 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Benicia, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00049219. Retrieved from https://blissgarden.com/california/benicia.
When to Plant in Benicia, CA — Frost Dates & Zone 9b — BlissGarden