What Planting Zones Are in Texas?
Texas spans USDA hardiness zones 6b to 10b, where the average coldest winter night ranges from −5 °F to 40 °F (−20.6 °C to 4.4 °C). Zone 8b covers the most ZIP codes, 38%, and zones 8a to 9b together cover 89% of the state.
- Zone 6b<1% · 4 ZIPs
- Zone 7a4% · 94 ZIPs
- Zone 7b3% · 88 ZIPs
- Zone 8a13% · 333 ZIPs
- Zone 8b38% · 978 ZIPs
- Zone 9a22% · 555 ZIPs
- Zone 9b16% · 423 ZIPs
- Zone 10a4% · 95 ZIPs
- Zone 10b<1% · 1 ZIP
Bars show each zone's share of the 2,571 Texas ZIP codes in the official 2023 USDA ZIP code table; select a zone for its temperatures and hardy plants.
What Hardiness Zone Are Texas Cities In?
Houston is in zone 9b, San Antonio is in zone 9a, Dallas is in zone 8b and Fort Worth is in zone 8b. The table lists the zone, winter low and average frost dates for 18 Texas cities, using the ZIP code nearest each city center.
| City | ZIP | Zone | Winter low | Last frost | First frost |
|---|---|---|---|---|---|
| Houston | 77009 | 9b | 25 °F to 30 °F | Feb 2 | Dec 25 |
| San Antonio | 78201 | 9a | 20 °F to 25 °F | Feb 25 | Nov 28 |
| Dallas | 75246 | 8b | 15 °F to 20 °F | Mar 2 | Nov 29 |
| Fort Worth | 76164 | 8b | 15 °F to 20 °F | Mar 5 | Nov 24 |
| Austin | 78703 | 9a | 20 °F to 25 °F | Feb 20 | Dec 3 |
| El Paso | 79904 | 8b | 15 °F to 20 °F | Mar 2 | Nov 20 |
| Arlington | 76015 | 8b | 15 °F to 20 °F | Mar 9 | Nov 21 |
| Corpus Christi | 78373 | 10a | 30 °F to 35 °F | Jan 22 | Jan 4 |
| Plano | 75023 | 8b | 15 °F to 20 °F | Mar 7 | Nov 21 |
| Lubbock | 79410 | 7b | 5 °F to 10 °F | Mar 24 | Nov 11 |
| Laredo | 78041 | 9b | 25 °F to 30 °F | Jan 20 | Dec 25 |
| Amarillo | 79101 | 7a | 0 °F to 5 °F | Apr 15 | Oct 29 |
| Brownsville | 78526 | 10a | 30 °F to 35 °F | Jan 9 | Jan 4 |
| Denton | 76201 | 8a | 10 °F to 15 °F | Mar 13 | Nov 20 |
| Killeen | 76541 | 8b | 15 °F to 20 °F | Mar 14 | Nov 17 |
| Pasadena | 77505 | 9b | 25 °F to 30 °F | Jan 30 | Dec 28 |
| McAllen | 78501 | 10a | 30 °F to 35 °F | Jan 9 | Jan 1 |
| Waco | 76710 | 8b | 15 °F to 20 °F | Mar 9 | Nov 20 |
Zone: 2023 USDA ZIP code table for the ZIP code nearest each city's Census center point. Frost dates: 50% (median) dates from the nearest NOAA station, 1991–2020 normals. Cities: the largest Texas places by 2024 Census population estimates, spread across the state, plus the largest place in each common zone. Large cities can span two half zones.
Which Parts of Texas Are in Each Zone?
Zone 6b, the coldest Texas zone, covers <1% of ZIP codes around Dalhart. Zone 10a, the warmest with towns, covers 4% around Corpus Christi, Brownsville and McAllen. The table lists the largest places in every zone.
| Zone | Avg. coldest night | Share of ZIPs | Largest places in this zone |
|---|---|---|---|
| Zone 6b | −5 °F to 0 °F | <1% (4) | Dalhart |
| Zone 7a | 0 °F to 5 °F | 4% (94) | Amarillo, Pampa, Canyon, Hereford |
| Zone 7b | 5 °F to 10 °F | 3% (88) | Lubbock, Plainview, Levelland, Wolfforth |
| Zone 8a | 10 °F to 15 °F | 13% (333) | Denton, Abilene, Wichita Falls, San Angelo |
| Zone 8b | 15 °F to 20 °F | 38% (978) | Dallas, Fort Worth, El Paso, Arlington |
| Zone 9a | 20 °F to 25 °F | 22% (555) | San Antonio, Austin, Round Rock, College Station |
| Zone 9b | 25 °F to 30 °F | 16% (423) | Houston, Laredo, Pasadena, Pearland |
| Zone 10a | 30 °F to 35 °F | 4% (95) | Corpus Christi, Brownsville, McAllen, Edinburg |
| Zone 10b | 35 °F to 40 °F | <1% (1) | Rural ZIP codes only |
Places: incorporated places with 1,000+ residents, assigned the zone of the ZIP code nearest their Census center point.
What Do the Hardiness Zones Mean for Texas Gardeners?
A Texas gardener in zone 10b sees winter lows about 40 °F milder than one in zone 6b, so a shrub or perennial that thrives in one part of the state can die in another. Choose plants rated to your own ZIP code's zone or colder.
Hardiness zones follow latitude, elevation and large bodies of water rather than state lines. Higher ground and inland valleys that trap cold air usually sit in colder half zones, while cities, coasts and large lakes moderate winter lows. Within Texas, a plant labelled “zones 8–9” survives winter in at least 89% of ZIP codes, but plants at the edge of their range benefit from mulch and a sheltered spot. Enter a ZIP code in the USDA hardiness zone finder by ZIP code to check your exact half zone before buying perennials.
A zone describes winter cold only. Summer heat, humidity, rainfall and soil decide whether a cold-hardy plant thrives, and planting dates for vegetables follow frost dates, not zones: two Texas towns in the same zone can have last frosts weeks apart.
What Plants Grow Well Across Texas?
182 plants in PlantoScan's catalogue are hardy in every zone from 8a to 9b, the zones that cover 89% of Texas ZIP codes. Popular examples include hydrangea, chrysanthemum and poppy.
Hydrangea
Hydrangea macrophylla
Zone 5 – 9
AI generated
Chrysanthemum
Chrysanthemum morifolium
Zone 5a – 9b
PlantoscanAI generated
Poppy
Papaver somniferum
Zone 3a – 9b
AI generated
- DahliaDahlia pinnataPlantoScan
Dahlia
Dahlia pinnata
Zone 8a – 11b
Carnation
Dianthus caryophyllus
Zone 5a – 9b
AI generated
Azalea
Azalea indica
Zone 6a – 9b
AI generated
Arugula
Eruca sativa
Zone 5a – 10b
AI generated
Alfalfa
Medicago sativa
Zone 3a – 10a
AI generated
Calla Lily
Zantedeschia aethiopica
Zone 8a – 10b
AI generated
Hardiness ranges come from PlantoScan's plant database; gardeners in Texas's colder or warmer edge zones should check each plant's full range.
When Is the Last Frost in Texas?
Across most Texas ZIP codes, the average last spring frost falls between February 2 and April 1, from January 9 in Brownsville to April 15 in Amarillo. Tender vegetables such as tomatoes go out 1 to 2 weeks after the local date.
The last and first frost dates for Texas cities include the safer 90% planting date, the fall frost date, growing season length and a tomato planting table for each city.
Frequently Asked Questions
- What planting zone is Texas?
- Texas spans USDA hardiness zones 6b to 10b on the 2023 USDA Plant Hardiness Zone Map. Zone 8b is the most common, covering 38% of the state's 2,571 ZIP codes, and zones 8a to 9b together cover 89%.
- What hardiness zone is Houston, Texas?
- Houston is in USDA hardiness zone 9b (ZIP 77009), where the average coldest winter night reaches 25 °F to 30 °F. Its average last spring frost is February 2 and its first fall frost December 25.
- What hardiness zone is San Antonio, Texas?
- San Antonio is in USDA hardiness zone 9a (ZIP 78201), where the average coldest winter night reaches 20 °F to 25 °F. Its average last spring frost is February 25 and its first fall frost November 28.
- What hardiness zone is Dallas, Texas?
- Dallas is in USDA hardiness zone 8b (ZIP 75246), where the average coldest winter night reaches 15 °F to 20 °F. Its average last spring frost is March 2 and its first fall frost November 29.
- What is the coldest hardiness zone in Texas?
- Zone 6b (−5 °F to 0 °F) is the coldest zone in Texas, found in 4 ZIP codes around Dalhart. The warmest is zone 10b (35 °F to 40 °F).
Zones: 2023 USDA Plant Hardiness Zone Map ZIP code table, USDA Agricultural Research Service and the PRISM Climate Group, Oregon State University, used without changes. Frost dates: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals. City locations and populations: U.S. Census Bureau Gazetteer files and Vintage 2024 population estimates. PlantoScan is not affiliated with or endorsed by these agencies.