Frost dates for 78254 — San Antonio, TX
How San Antonio compares
- In 8 years out of 10, the last spring frost in San Antonio falls between January 18 and March 16, a 57-day window. The first fall frost falls between November 17 and January 13.
- The median last frost is 25 days earlier than the Texas median of Mar 15.
- Its 294-day growing season is longer than 95% of the 1,316 Texas places with a regular frost season (state median 245 days).
- The last frost is 13 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 18 |
| 50% (median) | February 18 |
| 10% (safe for tender plants) | March 16 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 17 |
| 50% (median) | December 9 |
| 90% (late) | January 13 |
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 78254 — San Antonio, TX — last frost Feb 18, first frost Dec 9, zone 9a. whenisthelastfrost.com
When to plant vegetables in San Antonio, TX
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Nov 26 – Dec 10 | Jan 21 – Feb 4 | — | — |
| Peppers | Dec 10 – Dec 24 | Mar 4 – Mar 18 | — | — |
| Eggplant | Dec 10 – Dec 24 | Mar 4 – Mar 18 | — | — |
| Tomatoes | Dec 24 – Jan 7 | Feb 25 – Mar 11 | — | — |
| Lettuce | Dec 24 – Jan 7 | Jan 28 – Feb 11 | Jan 21 – Feb 25 | Oct 14 – Nov 11 |
| Kale | Dec 24 – Jan 7 | Jan 21 – Feb 4 | Jan 21 – Feb 4 | Sep 30 – Oct 21 |
| Broccoli | Dec 24 – Jan 7 | Feb 4 – Feb 18 | — | Sep 2 – Sep 23 |
| Cabbage | Dec 24 – Jan 7 | Jan 28 – Feb 11 | — | Sep 2 – Sep 23 |
| Cauliflower | Dec 24 – Jan 7 | Feb 4 – Feb 18 | — | Sep 2 – Sep 23 |
| Okra | Jan 7 – Jan 21 | Mar 11 – Mar 25 | Mar 11 – Mar 25 | — |
| Basil | Jan 7 – Jan 21 | Feb 25 – Mar 11 | — | — |
| Peas | — | — | Jan 7 – Jan 28 | Sep 16 – Oct 7 |
| Spinach | — | — | Jan 7 – Jan 28 | Oct 14 – Nov 4 |
| Radishes | — | — | Jan 14 – Feb 25 | Oct 28 – Nov 18 |
| Cucumbers | Jan 21 – Jan 28 | Mar 4 – Mar 11 | Feb 25 – Mar 11 | Sep 23 – Oct 7 |
| Zucchini & Summer Squash | Jan 21 – Jan 28 | — | Feb 25 – Mar 11 | Sep 30 – Oct 14 |
| Winter Squash & Pumpkins | Jan 21 – Jan 28 | — | Feb 25 – Mar 11 | — |
| Melons & Watermelon | Jan 21 – Jan 28 | Mar 4 – Mar 18 | — | — |
| Carrots | — | — | Jan 28 – Feb 25 | Sep 16 – Sep 30 |
| Beets | — | — | Jan 28 – Feb 25 | Sep 30 – Oct 14 |
| Potatoes | — | — | Jan 28 – Feb 18 | — |
| Swiss Chard | — | — | Feb 4 – Mar 4 | Sep 30 – Oct 14 |
| Cilantro | — | — | Feb 4 – Feb 25 | Oct 14 – Nov 4 |
| Green Beans | — | — | Feb 25 – Mar 18 | Sep 23 – Oct 7 |
| Sweet Corn | — | — | Feb 25 – Mar 11 | — |
| Sweet Potatoes | — | Mar 4 – Mar 25 | — | — |
| Garlic | — | — | — | Nov 25 – Dec 30 |
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/Seaworld, TX weather station, 12 km away (elevation 942 ft (287 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
- Helotes Mar 15 · Nov 13
- Rio Medina Feb 18 · Dec 9
- Mico Feb 18 · Dec 9
- Pipe Creek Mar 15 · Nov 13
- Castroville Feb 24 · Dec 2
- Macdona Feb 22 · Dec 2
- Jbsa Ft Sam Houston Feb 25 · Nov 28
- Jbsa Lackland Feb 25 · Nov 28
Frequently asked questions
When is the last frost in San Antonio, TX?
The median last spring frost in San Antonio, TX is February 18. There is still about a 10% chance of frost after March 16, 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 9, with about a 10% chance of frost before November 17.
How long is the growing season in San Antonio, TX?
About 294 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.