In San Antonio, TX, the average last spring frost is Feb 26 and the average first fall frost is Nov 28, which leaves about 277 frost-free days for the garden. These dates come from NOAA climate normals for the San Antonio International Airport, TX weather station, at 789 feet above sea level.
A very long season allows two full rounds of vegetables. Plant cool-season crops early and again in fall, and plan warm-season crops so they finish before the hottest part of summer. Frost timing varies from year to year: in about 1 spring in 10 the last frost falls as late as Mar 17, and in about 1 fall in 10 the first frost arrives as early as Nov 7.
Frost dates for San Antonio, TX
| Chance of a freeze (32°F) after or before this date | Last spring frost | First fall frost | Freeze-free season |
|---|---|---|---|
| Optimistic (about 1 year in 10) | Jan 29 | Dec 22 | 327 days |
| Average (half of years) | Feb 26 | Nov 28 | 277 days |
| Cautious (9 years in 10 are safe) | Mar 17 | Nov 7 | 235 days |
Source: NOAA NCEI U.S. Climate Normals, 1991 to 2020. Use the cautious dates for tender crops such as tomatoes and peppers.
When to plant in San Antonio, TX
These windows count weeks forward and back from the average frost dates above. They are planning guides: check the forecast before planting tender crops, and see our what to plant now tool for today's date.
| Crop | Start seeds indoors | Plant outdoors in spring | Plant in fall |
|---|---|---|---|
| Tomatoes | Jan 1 to Jan 15 | Mar 5 to Mar 12 | – |
| Peppers | Dec 18 to Jan 1 | Mar 12 to Mar 19 | – |
| Eggplant | Dec 18 to Jan 1 | Mar 12 to Mar 19 | – |
| Onions | Dec 18 to Jan 1 | Jan 29 to Feb 12 | – |
| Parsley | Dec 18 to Jan 1 | Feb 26 to Mar 5 | – |
| Broccoli, cabbage, cauliflower | Jan 1 to Jan 15 | Feb 12 to Feb 19 | Sep 5 to Oct 3 |
| Basil | Jan 15 to Jan 15 | Mar 5 to Mar 12 | – |
| Peas | Sow outdoors | Jan 15 to Jan 29 | Sep 5 to Oct 3 |
| Spinach | Sow outdoors | Jan 15 to Jan 29 | Oct 3 to Oct 31 |
| Radishes | Sow outdoors | Jan 15 to Jan 29 | Oct 3 to Oct 31 |
| Lettuce | Sow outdoors | Jan 29 to Feb 12 | Oct 3 to Oct 31 |
| Carrots | Sow outdoors | Jan 29 to Feb 12 | Sep 5 to Oct 3 |
| Beets | Sow outdoors | Jan 29 to Feb 12 | Sep 5 to Oct 3 |
| Potatoes | Sow outdoors | Jan 29 to Feb 12 | – |
| Kale | Sow outdoors | Jan 29 to Feb 12 | Sep 5 to Oct 3 |
| Swiss chard | Sow outdoors | Feb 12 to Feb 26 | – |
| Cilantro | Sow outdoors | Feb 12 to Feb 26 | Oct 3 to Oct 31 |
| Dill | Sow outdoors | Feb 26 to Mar 5 | – |
| Bush beans | Sow outdoors | Mar 5 to Mar 12 | Aug 25 to Sep 8 |
| Pole beans | Sow outdoors | Mar 5 to Mar 12 | – |
| Sweet corn | Sow outdoors | Mar 5 to Mar 12 | – |
| Cucumbers | Sow outdoors | Mar 5 to Mar 12 | Aug 15 to Aug 29 |
| Zucchini and summer squash | Sow outdoors | Mar 5 to Mar 12 | Aug 25 to Sep 8 |
| Winter squash | Sow outdoors | Mar 5 to Mar 12 | – |
| Sweet potatoes (slips) | Sow outdoors | Mar 12 to Mar 26 | – |
| Okra | Sow outdoors | Mar 12 to Mar 26 | – |
A dash in the fall column means the crop is not usually planted in fall, or the season is too short.
Overnight lows this week
No frost is forecast in the next week, according to the National Weather Service.
| Night | Forecast low | Frost risk |
|---|---|---|
| Sun 15 night | 58°F | No frost expected |
| Sun 15 night | 50°F | No frost expected |
| Mon 16 night | 49°F | No frost expected |
| Tue 17 night | 53°F | No frost expected |
| Wed 18 night | 61°F | No frost expected |
| Thu 19 night | 61°F | No frost expected |
| Fri 20 night | 62°F | No frost expected |
Live forecast for the station location, from the National Weather Service. For your own ZIP code, use our garden weather forecast.
More garden tools for San Antonio, TX
- Frost dates by ZIP code for your exact location
- What to plant now, based on today's date
- Garden weather forecast by ZIP code
- Safe transplant date calculator
Frequently asked questions
When is the last frost in San Antonio, TX?
The average last spring frost is Feb 26. A late frost as far out as Mar 17 happens in about 1 year in 10, so tender plants such as tomatoes and peppers are safest after that cautious date.
When is the first frost in San Antonio, TX?
The average first fall frost is Nov 28. It can arrive as early as Nov 7 in about 1 year in 10, so plan to harvest tender crops before then.
How long is the growing season in San Antonio, TX?
The average freeze-free season is about 277 days, between the average last spring frost and the average first fall frost.
Where do these dates come from?
They come from the NOAA 1991 to 2020 U.S. Climate Normals for the San Antonio International Airport, TX station. Hills, valleys, lakes and city heat can shift frost by a week or more, so compare with neighbors who garden near you.