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When to plant in Cibolo, TX

USDA Zone 9a

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

Cibolo enjoys a long ~287-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. In zone 9a, frost is a minor factor for Cibolo — most perennials thrive, and annual vegetables can go out early and stay late.

Station · RANDOLPH AFB · 5.9 km
Last spring frost
February 21
50% chance · 32°F
First fall frost
December 5
50% chance · 32°F
Growing season
287 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for CiboloA year-band showing 32°F frost risk from January to December for Cibolo: last spring frost around February 21, first fall frost around December 5, about 287 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

RANDOLPH AFB · 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 Cibolo’s own odds, recorded at RANDOLPH AFB.

Frost-probability curves for CiboloProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 21 and the first fall frost around December 5, giving about 287 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 26Mar 6Feb 13Nov 4Nov 24Dec 10
32°FMar 14Feb 21Jan 10Nov 16Dec 5Jan 1
28°FMar 5Jan 26Dec 18Nov 28Dec 19Feb 1

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

Nearby weather stations

3 within 24 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.

RANDOLPH AFB
Primary
6 km · 232 m elevation
SPRING
Feb 21
FALL
Dec 5
NEW BRAUNFELS
12 km · 220 m elevation
SPRING
Mar 8
FALL
Nov 18
AUSTIN SAN ANTONIO
24 km · 193 m elevation
SPRING
Mar 1
FALL
Nov 26

Cibolo planting FAQ

When is the last spring frost in Cibolo, TX?

On average, the last spring frost in Cibolo is around February 21 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Cibolo, TX?

In Cibolo, the first 32°F freeze of fall lands around December 5 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Cibolo in?

Cibolo is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Cibolo?

Cibolo has about 287 frost-free days — a long growing season — between the average last spring frost (February 21) and first fall frost (December 5).

When should I plant tomatoes in Cibolo?

For Cibolo, sow tomatoes indoors about December 27–January 10 and move the seedlings out around February 28, after the last spring frost.

Planting reminders

Never miss a window in Cibolo

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

Nearby cities

8 within reach

Frost dates recorded at RANDOLPH AFB, 6 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 Cibolo, TX — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00012911. Retrieved from https://blissgarden.com/texas/cibolo.