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When to plant in Rocklin, CA

USDA Zone 9b

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

Rocklin enjoys a long ~283-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. Heads up: the nearest complete-normals station is about 18 km from Rocklin, 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 Rocklin can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · AUBURN · 18.2 km
Last spring frost
February 25
50% chance · 32°F
First fall frost
December 5
50% chance · 32°F
Growing season
283 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for RocklinA year-band showing 32°F frost risk from January to December for Rocklin: last spring frost around February 25, first fall frost around December 5, about 283 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Rocklin is now 10 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

AUBURN · 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 Rocklin’s own odds, recorded at AUBURN.

Frost-probability curves for RocklinProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 25 and the first fall frost around December 5, giving about 283 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 30Apr 5Mar 2Oct 30Nov 19Dec 7
32°FApr 7Feb 25Jan 15Nov 15Dec 5Dec 31
28°FFeb 25Jan 13Dec 19Dec 1Dec 22Jan 22

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

Nearby weather stations

3 within 32 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.

AUBURN
Primary
18 km · 394 m elevation
SPRING
Feb 25
FALL
Dec 5
SACRAMENTO 5 ESE
31 km · 12 m elevation
SPRING
Jan 12
FALL
Dec 16
SACRAMENTO METRO AP
32 km · 7 m elevation
SPRING
Feb 22
FALL
Nov 24

Rocklin planting FAQ

When is the last spring frost in Rocklin, CA?

Rocklin's average last spring frost falls near February 25 — 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 Rocklin, CA?

In Rocklin, 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 Rocklin in?

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

How long is the growing season in Rocklin?

There are roughly 283 frost-free days in Rocklin (a long growing season), running from the average last frost around February 25 to the first fall frost near December 5.

When should I plant tomatoes in Rocklin?

In Rocklin, start tomato seeds indoors around December 31–January 14, then transplant seedlings outdoors around March 4 once the danger of frost has passed.

Planting reminders

Never miss a window in Rocklin

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

Nearby cities

8 within reach

Frost dates recorded at AUBURN, 18 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 Rocklin, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00040383. Retrieved from https://blissgarden.com/california/rocklin.