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When to plant in San Antonio, TX

USDA Zone 9a

Everything below — frost dates, hardiness zone, and what to plant when in San Antonio, Texas — is derived from the closest NOAA station with complete climate normals.

A generous ~276-day season lets San Antonio gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 9a is warm enough that San Antonio can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SAN ANTONIO INCARNATE WORD · 5.1 km
Last spring frost
February 25
50% chance · 32°F
First fall frost
November 28
50% chance · 32°F
Growing season
276 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for San AntonioA year-band showing 32°F frost risk from January to December for San Antonio: last spring frost around February 25, first fall frost around November 28, about 276 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SAN ANTONIO INCARNATE WORD · 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 San Antonio’s own odds, recorded at SAN ANTONIO INCARNATE WORD.

Frost-probability curves for San AntonioProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 25 and the first fall frost around November 28, giving about 276 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°FApr 2Mar 10Feb 18Oct 30Nov 16Dec 3
32°FMar 19Feb 25Jan 28Nov 7Nov 28Dec 21
28°FMar 5Feb 5Dec 31Nov 19Dec 15Jan 20

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowin 20 days
Brussels Sprouts
August 8August 22

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in San Antonio, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 11 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 ANTONIO INCARNATE WORD
Primary
5 km · 213 m elevation
SPRING
Feb 25
FALL
Nov 28
SAN ANTONIO INTL AP
10 km · 241 m elevation
SPRING
Feb 26
FALL
Nov 28
SAN ANTONIO KELLY AFB
11 km · 208 m elevation
SPRING
Feb 22
FALL
Dec 2

San Antonio planting FAQ

When is the last spring frost in San Antonio, TX?

On average, the last spring frost in San Antonio is around February 25 (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 San Antonio, TX?

Expect San Antonio's first fall frost near November 28 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is San Antonio in?

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

How long is the growing season in San Antonio?

There are roughly 276 frost-free days in San Antonio (a long growing season), running from the average last frost around February 25 to the first fall frost near November 28.

When should I plant tomatoes in San Antonio?

In San Antonio, start tomato seeds indoors around December 31–January 14, then transplant seedlings outdoors around March 4 once the danger of frost has passed.

Planting reminders

Never miss a window in San Antonio

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

Nearby cities

8 within reach

Frost dates recorded at SAN ANTONIO INCARNATE WORD, 5 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 San Antonio, TX — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00417947. Retrieved from https://blissgarden.com/texas/san-antonio.