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When to plant in Lemon Grove, CA

USDA Zone 10b

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

A generous ~349-day season lets Lemon Grove gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 10b, frost is a minor factor for Lemon Grove — most perennials thrive, and annual vegetables can go out early and stay late.

Station · EL CAJON · 12.5 km
Last spring frost
January 6
50% chance · 32°F
First fall frost
December 21
50% chance · 32°F
Growing season
349 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Lemon GroveA year-band showing 32°F frost risk from January to December for Lemon Grove: last spring frost around January 6, first fall frost around December 21, about 349 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Lemon Grove is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

EL CAJON · 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 Lemon Grove’s own odds, recorded at EL CAJON.

Frost-probability curves for Lemon GroveProbability 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 21, giving about 349 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 3Feb 6Jan 6Nov 18Dec 6Dec 29
32°FFeb 7Jan 6Dec 13Dec 1Dec 21Jan 15
28°FJan 15Dec 31Dec 8Dec 7Dec 30Jan 14

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

Nearby weather stations

3 within 27 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.

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

Lemon Grove planting FAQ

When is the last spring frost in Lemon Grove, CA?

Plan for the last spring frost in Lemon Grove 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 Lemon Grove, CA?

In Lemon Grove, the first 32°F freeze of fall lands around December 21 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Lemon Grove in?

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

How long is the growing season in Lemon Grove?

Lemon Grove has about 349 frost-free days — a long growing season — between the average last spring frost (January 6) and first fall frost (December 21).

When should I plant tomatoes in Lemon Grove?

For Lemon Grove, sow tomatoes indoors about November 11–November 25 and move the seedlings out around January 13, after the last spring frost.

Planting reminders

Never miss a window in Lemon Grove

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

Nearby cities

8 within reach

Frost dates recorded at EL CAJON, 12 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 Lemon Grove, CA — Frost Dates & Zone 10b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00042706. Retrieved from https://blissgarden.com/california/lemon-grove.
When to Plant in Lemon Grove, CA — Frost Dates & Zone 10b — BlissGarden