Frost dates · USDA zone 9a
Frost dates for San Antonio, TX
San Antonio, TX sees its last 32 °F night of spring around February 25 and its first of fall around November 28 — a 277-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Jan 28 | Dec 21 |
| Median — 1 year in 2 | Feb 25 | Nov 28 |
| 1 year in 10 | Mar 19 | Nov 7 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 277 days median, at least 249 in 9 years of 10, at least 313 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Feb 5 and first of Dec 15.
San Antonio planting calendar, 2027
Every row runs from the median last frost (Feb 25) and median first frost (Nov 28) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Dec 3 | Jan 28 | May 18 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Feb 25 | Mar 27 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Feb 11 | Feb 11 | Mar 28 | 45 from sow |
| Genovese BasilGenovese | Jan 28 | Mar 11 | May 10 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Dec 31 | Mar 4 | May 18 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Dec 17 | Mar 11 | Jun 14 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Dec 31 | Mar 4 | May 18 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Dec 31 | Mar 4 | May 23 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Dec 31 | Mar 4 | May 23 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Feb 11 | Feb 11 | Apr 22 | 70 from sow |
| TomatilloToma Verde | Jan 14 | Mar 4 | May 13 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Jan 14 | Mar 4 | May 18 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Jan 14 | Mar 4 | May 23 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can San Antonio grow?
Each sauce, scheduled for a San Antonio container garden: when the first seeds go in and when enough fruit has ripened for one batch.
San Antonio frost questions
When is the last frost in San Antonio, TX?
The median last 32 °F freeze at SAN ANTONIO INCARNATE WORD, TX is February 25: half of years see a later one. One year in ten, a freeze still comes after March 19; nine years in ten, it comes after January 28. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in San Antonio, TX?
The median first 32 °F freeze of fall is November 28. One year in ten it arrives before November 7; nine years in ten, before December 21.
How long is the growing season in San Antonio, TX?
277 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 249 days; one year in ten, at least 313 days.
What growing zone is San Antonio, TX?
USDA hardiness zone 9a, per the 2023 USDA Plant Hardiness Zone Map for ZIP 78201. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in San Antonio, TX?
Start Roma VF (determinate paste) seeds indoors around Jan 14 and transplant around Mar 4, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for Mar 19. First ripe fruit lands around May 18.
When should I plant peppers in San Antonio, TX?
Sow jalapeño indoors on a heat mat around Dec 31; transplant no earlier than Mar 4, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around May 18.
Nearby in Texas
- Schertzlast frost Mar 8
- New Braunfelslast frost Feb 25
- San Marcoslast frost Feb 28
- Kylelast frost Feb 28
- Austinlast frost Feb 20
- Cedar Parklast frost Mar 11
All Texas frost dates → · How frost-date math drives a sowing calendar →