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When to plant in Patterson, CA

USDA Zone 9b

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

With about 308 frost-free days, Patterson supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Heads up: the nearest complete-normals station is about 24 km from Patterson, so your yard's frost dates can differ — a low spot or a paved city center can shift them by a week. Zone 9b is warm enough that Patterson can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · MODESTO CITY CO AP · 24.4 km
Last spring frost
January 31
50% chance · 32°F
First fall frost
December 5
50% chance · 32°F
Growing season
308 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for PattersonA year-band showing 32°F frost risk from January to December for Patterson: last spring frost around January 31, first fall frost around December 5, about 308 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Patterson is now 7 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

MODESTO CITY CO AP · 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 Patterson’s own odds, recorded at MODESTO CITY CO AP.

Frost-probability curves for PattersonProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 31 and the first fall frost around December 5, giving about 308 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 31Mar 1Feb 3Nov 8Nov 22Dec 9
32°FFeb 25Jan 31Dec 31Nov 20Dec 5Jan 6
28°FFeb 6Jan 8Dec 16Dec 1Dec 21Jan 20

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

What to plant now

TODAY · JULY 19
Fall sowin 27 days
Brussels Sprouts
August 15August 29

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

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

Nearby weather stations

3 within 27 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.

MODESTO CITY CO AP
Primary
24 km · 22 m elevation
SPRING
Jan 31
FALL
Dec 5
NEWMAN
25 km · 27 m elevation
SPRING
Feb 26
FALL
Nov 29
TURLOCK #2
27 km · 31 m elevation
SPRING
Jan 6
FALL
Dec 20

Patterson planting FAQ

When is the last spring frost in Patterson, CA?

Plan for the last spring frost in Patterson around January 31 (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 Patterson, CA?

In Patterson, the first 32°F freeze of fall lands around December 5 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Patterson in?

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

How long is the growing season in Patterson?

There are roughly 308 frost-free days in Patterson (a long growing season), running from the average last frost around January 31 to the first fall frost near December 5.

When should I plant tomatoes in Patterson?

In Patterson, start tomato seeds indoors around December 6–December 20, then transplant seedlings outdoors around February 7 once the danger of frost has passed.

Planting reminders

Never miss a window in Patterson

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

Nearby cities

8 within reach

Frost dates recorded at MODESTO CITY CO AP, 24 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 Patterson, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00023258. Retrieved from https://blissgarden.com/california/patterson.
When to Plant in Patterson, CA — Frost Dates & Zone 9b — BlissGarden