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When to plant in Santa Clara, CA

USDA Zone 9b

Everything below — frost dates, hardiness zone, and what to plant when in Santa Clara, California — is derived from the closest NOAA station with complete climate normals.

With about 344 frost-free days, Santa Clara supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 9b is warm enough that Santa Clara can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SAN JOSE · 3.9 km
Last spring frost
January 12
50% chance · 32°F
First fall frost
December 22
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 Santa ClaraA year-band showing 32°F frost risk from January to December for Santa Clara: last spring frost around January 12, first fall frost around December 22, about 344 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SAN JOSE · 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 Santa Clara’s own odds, recorded at SAN JOSE.

Frost-probability curves for Santa ClaraProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 12 and the first fall frost around December 22, 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°FMar 9Feb 12Jan 11Nov 17Dec 3Dec 31
32°FFeb 14Jan 12Dec 20Dec 1Dec 22Jan 20
28°FJan 17Dec 31Dec 10Dec 6Dec 28Jan 14

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 Santa Clara, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 8 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.

SAN JOSE
Primary
4 km · 16 m elevation
SPRING
Jan 12
FALL
Dec 22
SAN JOSE
6 km · 20 m elevation
SPRING
Jan 2
FALL
Dec 25
MOFFETT FEDERAL AIRFIELD
8 km · 12 m elevation
SPRING
Jan 6
FALL
Dec 23

Santa Clara planting FAQ

When is the last spring frost in Santa Clara, CA?

Santa Clara's average last spring frost falls near January 12 — 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 Santa Clara, CA?

The first fall frost in Santa Clara typically arrives around December 22 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Santa Clara in?

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

How long is the growing season in Santa Clara?

There are roughly 344 frost-free days in Santa Clara (a long growing season), running from the average last frost around January 12 to the first fall frost near December 22.

When should I plant tomatoes in Santa Clara?

In Santa Clara, start tomato seeds indoors around November 17–December 1, then transplant seedlings outdoors around January 19 once the danger of frost has passed.

Planting reminders

Never miss a window in Santa Clara

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

Nearby cities

8 within reach

Frost dates recorded at SAN JOSE, 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 Santa Clara, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00023293. Retrieved from https://blissgarden.com/california/santa-clara.
When to Plant in Santa Clara, CA — Frost Dates & Zone 9b — BlissGarden