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When to plant in Chico, CA

USDA Zone 9b

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Chico, California — all computed from Chico's nearest NOAA weather station.

A generous ~258-day season lets Chico gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 9b is warm enough that Chico can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · CHICO UNIV FARM · 7.6 km
Last spring frost
March 4
50% chance · 32°F
First fall frost
November 17
50% chance · 32°F
Growing season
258 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for ChicoA year-band showing 32°F frost risk from January to December for Chico: last spring frost around March 4, first fall frost around November 17, about 258 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Chico is now 9 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

CHICO UNIV FARM · 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 Chico’s own odds, recorded at CHICO UNIV FARM.

Frost-probability curves for ChicoProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around March 4 and the first fall frost around November 17, giving about 258 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 21Apr 5Mar 13Oct 21Nov 4Nov 19
32°FApr 2Mar 4Feb 8Nov 1Nov 17Dec 5
28°FMar 1Feb 5Jan 1Nov 13Dec 3Jan 5

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 9 days
Brussels Sprouts
July 28August 11
Fall sowin 23 days
Rutabaga
August 11August 25

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

Nearby weather stations

3 within 22 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.

CHICO UNIV FARM
Primary
8 km · 56 m elevation
SPRING
Mar 4
FALL
Nov 17
PARADISE
17 km · 533 m elevation
SPRING
Feb 7
FALL
Dec 18
DE SABLA
22 km · 826 m elevation
SPRING
Apr 17
FALL
Nov 11

Chico planting FAQ

When is the last spring frost in Chico, CA?

Chico's average last spring frost falls near March 4 — 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 Chico, CA?

The first fall frost in Chico typically arrives around November 17 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Chico in?

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

How long is the growing season in Chico?

There are roughly 258 frost-free days in Chico (a long growing season), running from the average last frost around March 4 to the first fall frost near November 17.

When should I plant tomatoes in Chico?

In Chico, start tomato seeds indoors around January 7–January 21, then transplant seedlings outdoors around March 11 once the danger of frost has passed.

Planting reminders

Never miss a window in Chico

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

Nearby cities

8 within reach

Frost dates recorded at CHICO UNIV FARM, 8 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 Chico, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00041715. Retrieved from https://blissgarden.com/california/chico.
When to Plant in Chico, CA — Frost Dates & Zone 9b — BlissGarden