Frost dates for 78244 — San Antonio, TX
How San Antonio compares
- In 8 years out of 10, the last spring frost in San Antonio falls between January 10 and March 14, a 63-day window. The first fall frost falls between November 16 and January 1.
- The median last frost is 22 days earlier than the Texas median of Mar 15.
- Its 287-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 10 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 12 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | January 10 |
| 50% (median) | February 21 |
| 10% (safe for tender plants) | March 14 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | November 16 |
| 50% (median) | December 5 |
| 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 78244 — San Antonio, TX — last frost Feb 21, first frost Dec 5, zone 9a. whenisthelastfrost.com
When to plant vegetables in San Antonio, TX
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Nov 29 – Dec 13 | Jan 24 – Feb 7 | — | — |
| Peppers | Dec 13 – Dec 27 | Mar 7 – Mar 21 | — | — |
| Eggplant | Dec 13 – Dec 27 | Mar 7 – Mar 21 | — | — |
| Tomatoes | Dec 27 – Jan 10 | Feb 28 – Mar 14 | — | — |
| Lettuce | Dec 27 – Jan 10 | Jan 31 – Feb 14 | Jan 24 – Feb 28 | Oct 10 – Nov 7 |
| Kale | Dec 27 – Jan 10 | Jan 24 – Feb 7 | Jan 24 – Feb 7 | Sep 26 – Oct 17 |
| Broccoli | Dec 27 – Jan 10 | Feb 7 – Feb 21 | — | Aug 29 – Sep 19 |
| Cabbage | Dec 27 – Jan 10 | Jan 31 – Feb 14 | — | Aug 29 – Sep 19 |
| Cauliflower | Dec 27 – Jan 10 | Feb 7 – Feb 21 | — | Aug 29 – Sep 19 |
| Okra | Jan 10 – Jan 24 | Mar 14 – Mar 28 | Mar 14 – Mar 28 | — |
| Basil | Jan 10 – Jan 24 | Feb 28 – Mar 14 | — | — |
| Peas | — | — | Jan 10 – Jan 31 | Sep 12 – Oct 3 |
| Spinach | — | — | Jan 10 – Jan 31 | Oct 10 – Oct 31 |
| Radishes | — | — | Jan 17 – Feb 28 | Oct 24 – Nov 14 |
| Cucumbers | Jan 24 – Jan 31 | Mar 7 – Mar 14 | Feb 28 – Mar 14 | Sep 19 – Oct 3 |
| Zucchini & Summer Squash | Jan 24 – Jan 31 | — | Feb 28 – Mar 14 | Sep 26 – Oct 10 |
| Winter Squash & Pumpkins | Jan 24 – Jan 31 | — | Feb 28 – Mar 14 | — |
| Melons & Watermelon | Jan 24 – Jan 31 | Mar 7 – Mar 21 | — | — |
| Carrots | — | — | Jan 31 – Feb 28 | Sep 12 – Sep 26 |
| Beets | — | — | Jan 31 – Feb 28 | Sep 26 – Oct 10 |
| Potatoes | — | — | Jan 31 – Feb 21 | — |
| Swiss Chard | — | — | Feb 7 – Mar 7 | Sep 26 – Oct 10 |
| Cilantro | — | — | Feb 7 – Feb 28 | Oct 10 – Oct 31 |
| Green Beans | — | — | Feb 28 – Mar 21 | Sep 19 – Oct 3 |
| Sweet Corn | — | — | Feb 28 – Mar 14 | — |
| Sweet Potatoes | — | Mar 7 – Mar 28 | — | — |
| Garlic | — | — | — | Nov 21 – Dec 26 |
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 Randolph Afb, TX weather station, 10 km away (elevation 761 ft (232 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
- Converse Feb 21 · Dec 5
- Universal City Feb 21 · Dec 5
- Schertz Feb 21 · Dec 5
- Adkins Feb 21 · Dec 5
- Jbsa Ft Sam Houston Feb 25 · Nov 28
- Jbsa Lackland Feb 25 · Nov 28
- Saint Hedwig Feb 21 · Dec 5
- Cibolo Feb 21 · Dec 5
Frequently asked questions
When is the last frost in San Antonio, TX?
The median last spring frost in San Antonio, TX is February 21. There is still about a 10% chance of frost after March 14, 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 5, with about a 10% chance of frost before November 16.
How long is the growing season in San Antonio, TX?
About 287 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.