blissgarden.

When to plant in Auburn, CA

USDA Zone 9b

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

With about 283 frost-free days, Auburn supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 9b is warm enough that Auburn can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · AUBURN · 1.5 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 AuburnA year-band showing 32°F frost risk from January to December for Auburn: 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 Auburn 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 Auburn’s own odds, recorded at AUBURN.

Frost-probability curves for AuburnProbability 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
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 Auburn, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 24 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
1 km · 394 m elevation
SPRING
Feb 25
FALL
Dec 5
GEORGETOWN RS
24 km · 915 m elevation
SPRING
Apr 12
FALL
Nov 21
COLFAX
24 km · 725 m elevation
SPRING
Apr 3
FALL
Nov 24

Auburn planting FAQ

When is the last spring frost in Auburn, CA?

Plan for the last spring frost in Auburn around February 25 (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 Auburn, CA?

In Auburn, 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 Auburn in?

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

How long is the growing season in Auburn?

There are roughly 283 frost-free days in Auburn (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 Auburn?

In Auburn, 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 Auburn

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

Nearby cities

8 within reach

Frost dates recorded at AUBURN, 1 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 Auburn, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00040383. Retrieved from https://blissgarden.com/california/auburn.
When to Plant in Auburn, CA — Frost Dates & Zone 9b — BlissGarden