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When to plant in Seal Beach, CA

USDA Zone 10a

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

With only about -4 frost-free days, Seal Beach has a short season — start heat-lovers indoors early, favor quick-maturing varieties, and use row cover to stretch both ends. These dates come from a station roughly 25 km away, the closest with full normals; terrain around Seal Beach (elevation, water, pavement) can move your real frost dates a few days either way. Zone 10a is warm enough that Seal Beach can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · TORRANCE AP · 25.5 km
Last spring frost
January 9
50% chance · 32°F
First fall frost
January 5
50% chance · 32°F
Growing season
-4 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Seal BeachA year-band from January to December for Seal Beach: Seal Beach is effectively frost-free at 32°F — no distinct frost season.
Seal Beach is effectively frost-free at 32°F — no distinct frost season.

Frost probability

TORRANCE AP · 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 Seal Beach’s own odds, recorded at TORRANCE AP.

Frost-probability curves for Seal BeachProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 9 and the first fall frost around January 5, where a 32°F freeze is rare enough that there is effectively no distinct frost season.
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 5Jan 17Dec 12Dec 1Dec 31Feb 20
32°FFeb 24Jan 9Dec 4Dec 3Jan 5Feb 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 Seal Beach, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 36 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.

TORRANCE AP
Primary
25 km · 27 m elevation
SPRING
Jan 9
FALL
Jan 5
TUSTIN IRVINE RCH
30 km · 72 m elevation
SPRING
Jan 5
FALL
Dec 25
LAGUNA BEACH
36 km · 13 m elevation
SPRING
Jan 6
FALL
Jan 2

Seal Beach planting FAQ

When is the last spring frost in Seal Beach, CA?

Seal Beach's average last spring frost falls near January 9 — 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 Seal Beach, CA?

Expect Seal Beach's first fall frost near January 5 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Seal Beach in?

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

How long is the growing season in Seal Beach?

There are roughly -4 frost-free days in Seal Beach (a short growing season), running from the average last frost around January 9 to the first fall frost near January 5.

When should I plant tomatoes in Seal Beach?

In Seal Beach, start tomato seeds indoors around November 14–November 28, then transplant seedlings outdoors around January 16 once the danger of frost has passed.

Planting reminders

Never miss a window in Seal Beach

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

Nearby cities

8 within reach

Frost dates recorded at TORRANCE AP, 25 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 Seal Beach, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00003122. Retrieved from https://blissgarden.com/california/seal-beach.
When to Plant in Seal Beach, CA — Frost Dates & Zone 10a — BlissGarden