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When to plant in Coronado, CA

USDA Zone 10b

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

Coronado enjoys a long ~359-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. These dates come from a station roughly 19 km away, the closest with full normals; terrain around Coronado (elevation, water, pavement) can move your real frost dates a few days either way. Zone 10b is warm enough that Coronado can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SAN DIEGO BROWN FLD · 19.1 km
Last spring frost
January 6
50% chance · 32°F
First fall frost
December 31
50% chance · 32°F
Growing season
359 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for CoronadoA year-band showing 32°F frost risk from January to December for Coronado: last spring frost around January 6, first fall frost around December 31, about 359 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SAN DIEGO BROWN FLD · 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 Coronado’s own odds, recorded at SAN DIEGO BROWN FLD.

Frost-probability curves for CoronadoProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 6 and the first fall frost around December 31, giving about 359 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 7Feb 2Dec 29Dec 1Dec 20Jan 25
32°FFeb 5Jan 6Dec 13Dec 11Dec 31Jan 30

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

Nearby weather stations

3 within 41 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 DIEGO BROWN FLD
Primary
19 km · 157 m elevation
SPRING
Jan 6
FALL
Dec 31
EL CAJON
27 km · 151 m elevation
SPRING
Jan 6
FALL
Dec 21
ALPINE
41 km · 517 m elevation
SPRING
Feb 12
FALL
Dec 24

Coronado planting FAQ

When is the last spring frost in Coronado, CA?

Plan for the last spring frost in Coronado around January 6 (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 Coronado, CA?

In Coronado, the first 32°F freeze of fall lands around December 31 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Coronado in?

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

How long is the growing season in Coronado?

There are roughly 359 frost-free days in Coronado (a long growing season), running from the average last frost around January 6 to the first fall frost near December 31.

When should I plant tomatoes in Coronado?

In Coronado, start tomato seeds indoors around November 11–November 25, then transplant seedlings outdoors around January 13 once the danger of frost has passed.

Planting reminders

Never miss a window in Coronado

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

Nearby cities

8 within reach

Frost dates recorded at SAN DIEGO BROWN FLD, 19 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 Coronado, CA — Frost Dates & Zone 10b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00003178. Retrieved from https://blissgarden.com/california/coronado.
When to Plant in Coronado, CA — Frost Dates & Zone 10b — BlissGarden