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Planting zones · San Antonio, Texas

What Planting Zone Is San Antonio?

San Antonio is in USDA zone 9a. South-central Texas: about 32 in. of rain, wettest in May, with August highs around 96°F. The median last freeze is February 26 and the first is November 28.

  • USDA zone (2023)9a
  • Coldest night (avg.)20 to 25°FZIP 78205
  • Median last frostFeb 2632°F
  • Median first frostNov 2832°F
  • Annual precipitation32 inches
  • Frost-free season277 days

San Antonio hardiness zone by ZIP code

On the 2023 USDA Plant Hardiness Zone Map, the ZIP codes we sampled in San Antonio fall in zone 9a; 78205 (zone 9a) has an average annual extreme minimum of 20 to 25°F. Choose perennials, shrubs, and trees rated at least to zone 9.

2023 USDA zone for sampled San Antonio ZIP codes
ZIPZoneAvg. coldest night
782059a20 to 25°F
782099a20 to 25°F
782459a20 to 25°F
782589a20 to 25°F

Not listed? Look up any ZIP code.

Frost dates and when to plant

The median last spring frost (32°F) at San Antonio Intl Airport is Feb 26 and the median first fall frost is Nov 28, a typical frost-free season of about 277 days.

Plant container perennials and shrubs after the median last frost (Feb 26), or in early fall at least six weeks before the median first frost (Nov 28) so roots can settle in before the ground freezes.

Rainfall and heat in San Antonio

Average annual precipitation is 32 inches (San Antonio Intl Airport, 1991–2020), spread across the year with May the wettest month and February the driest.

The average high in August is about 96°F and the average low in January is about 41°F, measured at about 790 ft.

That is why a zone rating alone isn't enough for a xeriscape here: pick plants that are both cold-hardy to zone 9 and rated very low or low water once established.

Low-water plants for San Antonio

52 plants in our database are hardy to zone 9 and suited to zone 9. Here are 12, driest first, across plant types.

See all zone 9 plants

Frequently asked questions

What planting zone is San Antonio?

San Antonio, TX is in USDA hardiness zone 9a on the 2023 USDA Plant Hardiness Zone Map, based on the ZIP codes we sampled (78205: 9a, 78209: 9a, 78245: 9a, 78258: 9a). In 78205, the average coldest night of the year is 20 to 25°F.

When is the last frost in San Antonio?

The median last spring frost (32°F) at San Antonio Intl Airport is Feb 26 and the median first fall frost is Nov 28, a typical frost-free season of about 277 days.

How much rain does San Antonio get?

Average annual precipitation is 32 inches (San Antonio Intl Airport, 1991–2020), spread across the year with May the wettest month and February the driest.

Sources

  1. NOAA NCEI U.S. Climate Normals 1991–2020, San Antonio Intl Airport (USW00012921). ncei.noaa.gov
  2. USDA ARS 2023 Plant Hardiness Zone Map, by ZIP. planthardiness.ars.usda.gov