San Antonio International Airport, TX Frost Dates & Growing Season

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

Last spring frost
Feb 26
~50% chance of frost after
First fall frost
Nov 28
~50% chance of frost before
Growing season
275 days
frost-free stretch
USDA zone
≈ 9a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Jan 29 Feb 26 Mar 17
First fall frost Dec 22 Nov 28 Nov 7
Hard freeze (28°F), median last Feb 9 · first Dec 13

Computed from NOAA 1991–2020 climate normals at the SAN ANTONIO INTL AP station. "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 International Airport

Computed from San Antonio International Airport'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 Jan 1 – Jan 15 Mar 5 – Mar 12
🫑 Peppers Dec 18 – Jan 1 Mar 12 – Mar 19
🥬 Lettuce Jan 15 – Jan 29 Jan 29 – Feb 12 Jan 29 – Feb 26
🫛 Peas Jan 15 – Jan 29
🥕 Carrots Feb 5 – Feb 26
🥦 Broccoli Jan 8 – Jan 22 Feb 5 – Feb 19
🥬 Kale Jan 15 – Jan 29 Jan 29 – Feb 12 Jan 29 – Feb 12
🥒 Cucumbers Jan 29 – Feb 5 Mar 5 – Mar 12 Mar 5 – Mar 12
🥒 Zucchini Jan 29 – Feb 5 Mar 5 – Mar 12 Mar 5 – Mar 12
🫘 Green Beans (Bush) Mar 5 – Mar 12
🌽 Sweet Corn Mar 5 – Mar 12
🌿 Basil Jan 15 – Jan 29 Mar 5 – Mar 12 Mar 12 – Mar 19
🧄 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 International Airport's dates automatically after a lookup.

Reading the season in San Antonio International Airport

With roughly 275 frost-free days, San Antonio International Airport 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 International Airport, TX?

The average last spring frost in San Antonio International Airport is around Feb 26, 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 International Airport, TX?

The average first fall frost in San Antonio International Airport 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 International Airport?

About 275 frost-free days on average, from Feb 26 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 International Airport 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.