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When to plant in Folsom, CA

USDA Zone 9b

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

With about 338 frost-free days, Folsom supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Folsom's nearest full-normals station sits about 27 km out, so treat these as a close estimate — local microclimate can nudge your first and last frost. Zone 9b is warm enough that Folsom can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SACRAMENTO 5 ESE · 26.9 km
Last spring frost
January 12
50% chance · 32°F
First fall frost
December 16
50% chance · 32°F
Growing season
338 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for FolsomA year-band showing 32°F frost risk from January to December for Folsom: last spring frost around January 12, first fall frost around December 16, about 338 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Folsom is now 7 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

SACRAMENTO 5 ESE · 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 Folsom’s own odds, recorded at SACRAMENTO 5 ESE.

Frost-probability curves for FolsomProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 12 and the first fall frost around December 16, giving about 338 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 11Feb 12Jan 9Nov 15Dec 1Dec 29
32°FFeb 8Jan 12Dec 18Nov 28Dec 16Jan 14
28°FJan 22Dec 31Dec 13Dec 5Dec 25Jan 14

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

Nearby weather stations

3 within 28 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.

SACRAMENTO 5 ESE
Primary
27 km · 12 m elevation
SPRING
Jan 12
FALL
Dec 16
AUBURN
27 km · 394 m elevation
SPRING
Feb 25
FALL
Dec 5
PLACERVILLE
28 km · 564 m elevation
SPRING
Mar 31
FALL
Nov 21

Folsom planting FAQ

When is the last spring frost in Folsom, CA?

Folsom's average last spring frost falls near January 12 — 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 Folsom, CA?

The first fall frost in Folsom typically arrives around December 16 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Folsom in?

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

How long is the growing season in Folsom?

There are roughly 338 frost-free days in Folsom (a long growing season), running from the average last frost around January 12 to the first fall frost near December 16.

When should I plant tomatoes in Folsom?

In Folsom, start tomato seeds indoors around November 17–December 1, then transplant seedlings outdoors around January 19 once the danger of frost has passed.

Planting reminders

Never miss a window in Folsom

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

Nearby cities

8 within reach

Frost dates recorded at SACRAMENTO 5 ESE, 27 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 Folsom, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00023271. Retrieved from https://blissgarden.com/california/folsom.