Frost dates for 78210 — San Antonio, TX
How San Antonio compares
- In 8 years out of 10, the last spring frost in San Antonio falls between January 20 and March 13, a 52-day window. The first fall frost falls between November 12 and January 1.
- The median last frost is 23 days earlier than the Texas median of Mar 15.
- Its 286-day growing season is longer than 92% of the 1,316 Texas places with a regular frost season (state median 245 days).
- The last frost is 11 days earlier than the zone 9a median of Mar 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 9a chart.
- The weather station records an average of 14 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | January 20 |
| 50% (median) | February 20 |
| 10% (safe for tender plants) | March 13 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 12 |
| 50% (median) | December 3 |
| 90% (late) | January 1 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for San Antonio, TX
Frost dates for 78210 — San Antonio, TX — last frost Feb 20, first frost Dec 3, zone 9a. whenisthelastfrost.com
When to plant vegetables in San Antonio, TX
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Nov 28 – Dec 12 | Jan 23 – Feb 6 | — | — |
| Peppers | Dec 12 – Dec 26 | Mar 6 – Mar 20 | — | — |
| Eggplant | Dec 12 – Dec 26 | Mar 6 – Mar 20 | — | — |
| Tomatoes | Dec 26 – Jan 9 | Feb 27 – Mar 13 | — | — |
| Lettuce | Dec 26 – Jan 9 | Jan 30 – Feb 13 | Jan 23 – Feb 27 | Oct 8 – Nov 5 |
| Kale | Dec 26 – Jan 9 | Jan 23 – Feb 6 | Jan 23 – Feb 6 | Sep 24 – Oct 15 |
| Broccoli | Dec 26 – Jan 9 | Feb 6 – Feb 20 | — | Aug 27 – Sep 17 |
| Cabbage | Dec 26 – Jan 9 | Jan 30 – Feb 13 | — | Aug 27 – Sep 17 |
| Cauliflower | Dec 26 – Jan 9 | Feb 6 – Feb 20 | — | Aug 27 – Sep 17 |
| Okra | Jan 9 – Jan 23 | Mar 13 – Mar 27 | Mar 13 – Mar 27 | — |
| Basil | Jan 9 – Jan 23 | Feb 27 – Mar 13 | — | — |
| Peas | — | — | Jan 9 – Jan 30 | Sep 10 – Oct 1 |
| Spinach | — | — | Jan 9 – Jan 30 | Oct 8 – Oct 29 |
| Radishes | — | — | Jan 16 – Feb 27 | Oct 22 – Nov 12 |
| Cucumbers | Jan 23 – Jan 30 | Mar 6 – Mar 13 | Feb 27 – Mar 13 | Sep 17 – Oct 1 |
| Zucchini & Summer Squash | Jan 23 – Jan 30 | — | Feb 27 – Mar 13 | Sep 24 – Oct 8 |
| Winter Squash & Pumpkins | Jan 23 – Jan 30 | — | Feb 27 – Mar 13 | — |
| Melons & Watermelon | Jan 23 – Jan 30 | Mar 6 – Mar 20 | — | — |
| Carrots | — | — | Jan 30 – Feb 27 | Sep 10 – Sep 24 |
| Beets | — | — | Jan 30 – Feb 27 | Sep 24 – Oct 8 |
| Potatoes | — | — | Jan 30 – Feb 20 | — |
| Swiss Chard | — | — | Feb 6 – Mar 6 | Sep 24 – Oct 8 |
| Cilantro | — | — | Feb 6 – Feb 27 | Oct 8 – Oct 29 |
| Green Beans | — | — | Feb 27 – Mar 20 | Sep 17 – Oct 1 |
| Sweet Corn | — | — | Feb 27 – Mar 13 | — |
| Sweet Potatoes | — | Mar 6 – Mar 27 | — | — |
| Garlic | — | — | — | Nov 19 – Dec 24 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the San Antonio Stinson Ap, TX weather station, 7 km away (elevation 571 ft (174 m)).
ZIP codes in San Antonio: 78201 78202 78203 78204 78205 78206 78207 78208 78209 78210 78211 78212 78213 78214 78215 78216 78217 78218 78219 78220 78221 78222 78223 78224 78225 78226 78227 78228 78229 78230 78231 78232 78233 78235 78237 78238 78239 78240 78241 78242 78243 78244 78245 78246 78247 78248 78249 78250 78251 78252 78253 78254 78255 78256 78257 78258 78259 78260 78261 78263 …
Frost dates near San Antonio
- Jbsa Ft Sam Houston Feb 25 · Nov 28
- Jbsa Lackland Feb 25 · Nov 28
- Converse Feb 21 · Dec 5
- Adkins Feb 21 · Dec 5
- Elmendorf Feb 20 · Dec 3
- Macdona Feb 22 · Dec 2
- Universal City Feb 21 · Dec 5
- Von Ormy Feb 22 · Dec 2
Frequently asked questions
When is the last frost in San Antonio, TX?
The median last spring frost in San Antonio, TX is February 20. There is still about a 10% chance of frost after March 13, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in San Antonio, TX?
The median first fall frost is December 3, with about a 10% chance of frost before November 12.
How long is the growing season in San Antonio, TX?
About 286 days between the median last spring frost and first fall frost.
What planting zone is San Antonio, TX?
San Antonio, TX is in USDA hardiness zone 9a.