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When to plant in Ashland, CA

USDA Zone 10a

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

With about 357 frost-free days, Ashland supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 10a is warm enough that Ashland can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · HAYWARD AIR TERMINAL · 4.4 km
Last spring frost
January 2
50% chance · 32°F
First fall frost
December 25
50% chance · 32°F
Growing season
357 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for AshlandA year-band showing 32°F frost risk from January to December for Ashland: last spring frost around January 2, first fall frost around December 25, about 357 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Ashland is now 5 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

HAYWARD AIR TERMINAL · 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 Ashland’s own odds, recorded at HAYWARD AIR TERMINAL.

Frost-probability curves for AshlandProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 2 and the first fall frost around December 25, giving about 357 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°FFeb 28Jan 29Dec 30Nov 24Dec 12Jan 11
32°FJan 27Jan 2Dec 13Dec 6Dec 25Jan 20

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

Nearby weather stations

3 within 19 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.

HAYWARD AIR TERMINAL
Primary
4 km · 13 m elevation
SPRING
Jan 2
FALL
Dec 25
OAKLAND METRO INTL AP
10 km · 2 m elevation
SPRING
Jan 7
FALL
Dec 23
FREMONT
19 km · 12 m elevation
SPRING
Jan 7
FALL
Dec 22

Ashland planting FAQ

When is the last spring frost in Ashland, CA?

Plan for the last spring frost in Ashland around January 2 (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 Ashland, CA?

In Ashland, the first 32°F freeze of fall lands around December 25 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Ashland in?

Ashland is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Ashland?

There are roughly 357 frost-free days in Ashland (a long growing season), running from the average last frost around January 2 to the first fall frost near December 25.

When should I plant tomatoes in Ashland?

In Ashland, start tomato seeds indoors around November 7–November 21, then transplant seedlings outdoors around January 9 once the danger of frost has passed.

Planting reminders

Never miss a window in Ashland

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

Nearby cities

8 within reach

Frost dates recorded at HAYWARD AIR TERMINAL, 4 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 Ashland, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00093228. Retrieved from https://blissgarden.com/california/ashland.
When to Plant in Ashland, CA — Frost Dates & Zone 10a — BlissGarden