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When to plant in South Whittier, CA

USDA Zone 10b

South Whittier, California frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

South Whittier's growing season is short at roughly -2 days, so succession planting is limited; lean on transplants over direct sowing for anything slow to mature. Heads up: the nearest complete-normals station is about 18 km from South Whittier, so your yard's frost dates can differ — a low spot or a paved city center can shift them by a week. Zone 10b is warm enough that South Whittier can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SAN GABRIEL FIRE DEPT · 18.0 km
Last spring frost
January 4
50% chance · 32°F
First fall frost
January 2
50% chance · 32°F
Growing season
-2 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for South WhittierA year-band from January to December for South Whittier: South Whittier is effectively frost-free at 32°F — no distinct frost season.
South Whittier is effectively frost-free at 32°F — no distinct frost season.

Frost probability

SAN GABRIEL FIRE DEPT · 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 South Whittier’s own odds, recorded at SAN GABRIEL FIRE DEPT.

Frost-probability curves for South WhittierProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 4 and the first fall frost around January 2, 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°FFeb 20Jan 17Dec 20Dec 6Dec 26Jan 30
32°FJan 28Jan 4Dec 19Dec 18Jan 2Jan 26

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

Nearby weather stations

3 within 29 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.

SAN GABRIEL FIRE DEPT
Primary
18 km · 111 m elevation
SPRING
Jan 4
FALL
Jan 2
PASADENA
26 km · 263 m elevation
SPRING
Jan 8
FALL
Jan 7
POMONA/FAIRPLEX
29 km · 305 m elevation
SPRING
Jan 8
FALL
Dec 28

South Whittier planting FAQ

When is the last spring frost in South Whittier, CA?

South Whittier's average last spring frost falls near January 4 — 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 South Whittier, CA?

The first fall frost in South Whittier typically arrives around January 2 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is South Whittier in?

South Whittier is in USDA hardiness zone 10b. In zone 10b, winters are mild — many tender perennials overwinter here.

How long is the growing season in South Whittier?

There are roughly -2 frost-free days in South Whittier (a short growing season), running from the average last frost around January 4 to the first fall frost near January 2.

When should I plant tomatoes in South Whittier?

In South Whittier, start tomato seeds indoors around November 9–November 23, then transplant seedlings outdoors around January 11 once the danger of frost has passed.

Planting reminders

Never miss a window in South Whittier

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

Nearby cities

8 within reach

Frost dates recorded at SAN GABRIEL FIRE DEPT, 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 South Whittier, CA — Frost Dates & Zone 10b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00047785. Retrieved from https://blissgarden.com/california/south-whittier.
When to Plant in South Whittier, CA — Frost Dates & Zone 10b — BlissGarden