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When to plant in San Francisco, CA

USDA Zone 10a

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

San Francisco's growing season is short at roughly -5 days, so succession planting is limited; lean on transplants over direct sowing for anything slow to mature. Heads up: the nearest complete-normals station is about 46 km from San Francisco, so your yard's frost dates can differ — a low spot or a paved city center can shift them by a week. Zone 10a is warm enough that San Francisco can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SAN FRANCISCO OCEANSIDE · 46.3 km
Last spring frost
December 30
50% chance · 32°F
First fall frost
December 25
50% chance · 32°F
Growing season
-5 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for San FranciscoA year-band from January to December for San Francisco: San Francisco is effectively frost-free at 32°F — no distinct frost season.
San Francisco is effectively frost-free at 32°F — no distinct frost season.

The average first fall frost in San Francisco is now 8 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

SAN FRANCISCO OCEANSIDE · 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 San Francisco’s own odds, recorded at SAN FRANCISCO OCEANSIDE.

Frost-probability curves for San FranciscoProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around December 30 and the first fall frost around December 25, where a 32°F freeze is rare enough that there is effectively no distinct frost season.
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 7Jan 15Dec 11Nov 28Dec 26Feb 22
32°FMar 13Dec 30Dec 2Nov 26Dec 25Feb 13

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 San Francisco, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

2 within 50 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 FRANCISCO OCEANSIDE
Primary
46 km · 2 m elevation
SPRING
Dec 30
FALL
Dec 25
KENTFIELD
50 km · 44 m elevation
SPRING
Jan 16
FALL
Dec 18

San Francisco planting FAQ

When is the last spring frost in San Francisco, CA?

Plan for the last spring frost in San Francisco around December 30 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.

When is the first fall frost in San Francisco, CA?

The first fall frost in San Francisco typically arrives around December 25 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is San Francisco in?

San Francisco is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.

How long is the growing season in San Francisco?

There are roughly -5 frost-free days in San Francisco (a short growing season), running from the average last frost around December 30 to the first fall frost near December 25.

When should I plant tomatoes in San Francisco?

In San Francisco, start tomato seeds indoors around November 4–November 18, then transplant seedlings outdoors around January 6 once the danger of frost has passed.

Planting reminders

Never miss a window in San Francisco

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

Nearby cities

8 within reach

Frost dates recorded at SAN FRANCISCO OCEANSIDE, 46 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 San Francisco, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00047767. Retrieved from https://blissgarden.com/california/san-francisco.
When to Plant in San Francisco, CA — Frost Dates & Zone 10a — BlissGarden