San Antonio, TX Frost Dates & Growing Season

The two dates every San Antonio garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Feb 25
~50% chance of frost after
First fall frost
Nov 28
~50% chance of frost before
Growing season
276 days
frost-free stretch
USDA zone
9a
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Jan 28 Feb 25 Mar 19
First fall frost Dec 21 Nov 28 Nov 7
Hard freeze (28°F), median last Feb 5 · first Dec 15

Computed from NOAA 1991–2020 climate normals at the San Antonio Incarnate Word station (6 km from central San Antonio). "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for San Antonio

Computed from San Antonio's own frost dates. Click any crop for the full zone-9 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Dec 31 – Jan 14 Mar 4 – Mar 11
🫑 Peppers Dec 17 – Dec 31 Mar 11 – Mar 18
🥬 Lettuce Jan 14 – Jan 28 Jan 28 – Feb 11 Jan 28 – Feb 25
🫛 Peas Jan 14 – Jan 28
🥕 Carrots Feb 4 – Feb 25
🥦 Broccoli Jan 7 – Jan 21 Feb 4 – Feb 18
🥬 Kale Jan 14 – Jan 28 Jan 28 – Feb 11 Jan 28 – Feb 11
🥒 Cucumbers Jan 28 – Feb 4 Mar 4 – Mar 11 Mar 4 – Mar 11
🥒 Zucchini Jan 28 – Feb 4 Mar 4 – Mar 11 Mar 4 – Mar 11
🫘 Green Beans (Bush) Mar 4 – Mar 11
🌽 Sweet Corn Mar 4 – Mar 11
🌿 Basil Jan 14 – Jan 28 Mar 4 – Mar 11 Mar 11 – Mar 18
🧄 Garlic Fall: Oct 17 – Nov 14

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use San Antonio's dates automatically after a lookup.

Reading the season in San Antonio

With roughly 276 frost-free days, San Antonio gardens fit long-season crops — melons, winter squash, sweet potatoes — with room left for spring and fall rounds of greens and roots. The first frost around Nov 28 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in San Antonio, TX?

The average last spring frost in San Antonio is around Feb 25, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in San Antonio, TX?

The average first fall frost in San Antonio arrives around Nov 28. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in San Antonio?

About 276 frost-free days on average, from Feb 25 to Nov 28. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is San Antonio in?

USDA zone 9a on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.