San Antonio, TX planting zone & frost dates
San Antonio is in USDA hardiness zone 9a. The last spring frost usually comes around February 25 and the first fall frost around November 28, for a growing season of about 277 days.
Planting calendar for San Antonio
Dates are counted from the average last spring frost (February 25) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.
| Crop | When |
|---|---|
| Tomatoes | Start seeds indoors: Dec 31 – Jan 14 Transplant outdoors: Mar 4 – Mar 11 |
| Peppers | Start seeds indoors: Dec 17 – Dec 31 Transplant outdoors: Mar 11 – Mar 18 |
| Eggplant | Start seeds indoors: Dec 17 – Dec 31 Transplant outdoors: Mar 11 – Mar 18 |
| Broccoli | Start seeds indoors: Dec 17 – Dec 31 Transplant outdoors: Jan 28 – Feb 11 |
| Cabbage | Start seeds indoors: Dec 17 – Dec 31 Transplant outdoors: Jan 28 – Feb 11 |
| Onions (sets) | Plant outdoors: Jan 28 – Feb 11 |
| Peas | Sow outdoors: Jan 14 – Jan 28 |
| Spinach | Sow outdoors: Jan 14 – Jan 28 |
| Lettuce | Sow outdoors: Jan 28 – Feb 11 |
| Carrots | Sow outdoors: Jan 28 – Feb 11 |
| Potatoes | Plant outdoors: Jan 28 – Feb 11 |
| Beans | Sow outdoors: Mar 4 – Mar 11 |
| Sweet corn | Sow outdoors: Mar 4 – Mar 11 |
| Cucumbers | Sow outdoors: Mar 4 – Mar 11 |
| Squash & zucchini | Sow outdoors: Mar 4 – Mar 11 |
| Basil | Start seeds indoors: Jan 14 – Jan 28 Transplant outdoors: Mar 4 – Mar 11 |
Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 3 (8 weeks before the average first fall frost on Nov 28).
Useful for zone 9a gardens
- Seed starting kit with dome — to start seeds indoors before the last frost
- LED grow light for seedlings — stops leggy seedlings
- Frost cloth / plant covers — for late spring and early fall frosts
- Soil thermometer — warm-season crops need soil above 60°F
- Shade cloth — for hot summers
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Frost risk in detail
| 90% chance | 50% chance | 10% chance | |
|---|---|---|---|
| Last 32°F frost in spring is after | Jan 28 | Feb 25 | Mar 19 |
| First 32°F frost in fall is before | Dec 21 | Nov 28 | Nov 7 |
How to read it: in spring there is a 10% chance of a frost after March 19, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 7. A hard freeze (28°F) usually ends around February 5.
Hardiness zone by ZIP code in San Antonio
- 78201 zone 9a
- 78202 zone 9a
- 78203 zone 9a
- 78204 zone 9a
- 78205 zone 9a
- 78207 zone 9a
- 78208 zone 9a
- 78209 zone 9a
- 78210 zone 9a
- 78211 zone 9a
- 78212 zone 9a
- 78213 zone 9a
- 78214 zone 9a
- 78215 zone 9a
- 78216 zone 9a
- 78217 zone 9a
- 78218 zone 9a
- 78219 zone 9a
- 78220 zone 9a
- 78221 zone 9a
- 78222 zone 9a
- 78223 zone 9a
- 78224 zone 9a
- 78225 zone 9a
- 78226 zone 9a
- 78227 zone 9a
- 78228 zone 9a
- 78229 zone 9a
- 78230 zone 9a
- 78231 zone 9a
- 78232 zone 9a
- 78233 zone 9a
- 78235 zone 9a
- 78237 zone 9a
- 78238 zone 9a
- 78239 zone 9a
- 78240 zone 9a
- 78241 zone 9a
- 78242 zone 9a
- 78243 zone 9a
- 78244 zone 9a
- 78245 zone 9a
- 78246 zone 9a
- 78247 zone 9a
- 78248 zone 9a
- 78249 zone 9a
- 78250 zone 9a
- 78251 zone 9a
- 78252 zone 9a
- 78253 zone 9a
- 78254 zone 9a
- 78255 zone 8b
- 78256 zone 9a
- 78257 zone 9a
- 78258 zone 9a
- 78259 zone 9a
- 78260 zone 8b
- 78261 zone 9a
- 78263 zone 9a
- 78264 zone 9a
- 78265 zone 9a
- 78266 zone 9a
- 78268 zone 9a
- 78269 zone 9a
- 78270 zone 9a
- 78278 zone 9a
- 78279 zone 9a
- 78280 zone 9a
- 78283 zone 9a
- 78284 zone 9a
- 78285 zone 9a
- 78288 zone 9a
- 78289 zone 9a
- 78291 zone 9a
- 78292 zone 9a
- 78293 zone 9a
- 78294 zone 9a
- 78295 zone 9a
- 78296 zone 9a
- 78297 zone 9a
- 78298 zone 9a
- 78299 zone 9a
Nearby cities
- Converse zone 9a, last frost Feb 21
- Live Oak zone 9a, last frost Feb 21
- Universal City zone 9a, last frost Feb 21
- Schertz zone 9a, last frost Feb 21
- Timberwood Park zone 8b, last frost Feb 26
- Cibolo zone 9a, last frost Feb 21
- Boerne zone 8b, last frost Mar 15
- New Braunfels zone 9a, last frost Mar 8
Questions
What growing zone is San Antonio, TX?
San Antonio is in USDA Plant Hardiness Zone 9a (average extreme winter low 20°F to 25°F), according to the USDA 2023 map. Some ZIP codes of the city fall in zone 8b.
When is the last frost in San Antonio?
The average last spring frost (32°F) in San Antonio is February 25. There is still a 10% chance of frost until March 19.
When can I plant tomatoes in San Antonio?
Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Mar 4 – Mar 11. Start seeds indoors 6–8 weeks before the last frost.
Frost dates: NOAA U.S. Climate Normals 1991–2020, station San Antonio Incarnate Word, TX (USC00417947), 5.5 km (3.4 mi) from the city center, elevation 213 m, based on 16 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.