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When to plant in Gilroy, CA

USDA Zone 9b

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

A generous ~276-day season lets Gilroy gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 9b, frost is a minor factor for Gilroy — most perennials thrive, and annual vegetables can go out early and stay late.

Station · GILROY · 2.2 km
Last spring frost
February 24
50% chance · 32°F
First fall frost
November 27
50% chance · 32°F
Growing season
276 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for GilroyA year-band showing 32°F frost risk from January to December for Gilroy: last spring frost around February 24, first fall frost around November 27, about 276 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

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

Frost probability

GILROY · 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 Gilroy’s own odds, recorded at GILROY.

Frost-probability curves for GilroyProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 24 and the first fall frost around November 27, giving about 276 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°FMay 1Apr 4Mar 4Oct 20Nov 10Nov 29
32°FApr 4Feb 24Jan 23Nov 10Nov 27Dec 18
28°FFeb 19Jan 16Dec 22Nov 24Dec 12Jan 14

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 19 days
Brussels Sprouts
August 7August 21

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

Nearby weather stations

3 within 20 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.

GILROY
Primary
2 km · 59 m elevation
SPRING
Feb 24
FALL
Nov 27
WATSONVILLE WTR WKS
18 km · 29 m elevation
SPRING
Jan 28
FALL
Dec 13
WATSONVILLE MUNI AP
20 km · 49 m elevation
SPRING
Jan 31
FALL
Dec 9

Gilroy planting FAQ

When is the last spring frost in Gilroy, CA?

Gilroy's average last spring frost falls near February 24 — 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 Gilroy, CA?

The first fall frost in Gilroy typically arrives around November 27 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Gilroy in?

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

How long is the growing season in Gilroy?

Gilroy has about 276 frost-free days — a long growing season — between the average last spring frost (February 24) and first fall frost (November 27).

When should I plant tomatoes in Gilroy?

For Gilroy, sow tomatoes indoors about December 30–January 13 and move the seedlings out around March 3, after the last spring frost.

Planting reminders

Never miss a window in Gilroy

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

Nearby cities

8 within reach

Frost dates recorded at GILROY, 2 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 Gilroy, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00043417. Retrieved from https://blissgarden.com/california/gilroy.
When to Plant in Gilroy, CA — Frost Dates & Zone 9b — BlissGarden