Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 78207 — San Antonio, TX

ZIP code 78207 (San Antonio, Bexar County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 22 and the first fall frost December 2.

Where ZIP 78207 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostFeb 22
First frostDec 2
2012 zone9a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for San Antonio, TX…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in San Antonio, TX

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostFebruary 22median — 50% chance of a later frost
Safe for tender plantsMarch 12only 10% chance of frost after
First fall frostDecember 2median — 10% chance by Nov 13
Growing season284 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 1 and returns around December 16.

From the NOAA station San Antonio Kelly AFB, TX — 4 miles away, elevation 682 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 78207

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 11 – Jan 25
SpinachSow outdoors · Jan 11 – Feb 1
Broccoli, cabbageStart indoors · Dec 14 – Dec 28
Broccoli, cabbageTransplant · Feb 1 – Feb 15
Onion setsPlant outdoors · Jan 25 – Feb 8
PotatoesPlant outdoors · Feb 1 – Feb 15
LettuceSow outdoors · Jan 25 – Feb 8
Carrots, beetsSow outdoors · Feb 1 – Feb 15
TomatoesStart indoors · Dec 28 – Jan 11
TomatoesTransplant · Mar 1 – Mar 15
Peppers, eggplantStart indoors · Dec 14 – Dec 28
Peppers, eggplantTransplant · Mar 8 – Mar 22
BeansSow outdoors · Mar 1 – Mar 15
Sweet cornSow outdoors · Mar 1 – Mar 15
Cucumbers, squashSow outdoors · Mar 1 – Mar 15
Fall lettuce, spinachSow outdoors · Oct 7 – Oct 21
GarlicPlant cloves · Nov 18 – Dec 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 22) and first fall frost (Dec 2) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 78207 came on Jan 20 — 4 days earlier than the 1991–2020 average (Jan 24).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Soil in San Antonio, TX

The soil mapped at the center of ZIP 78207 is Lewisville — silty clay, well drained.

TextureSilty clayholds water and nutrients; slow to drain and warm up
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Lewisville silty clay, 0 to 1 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 78207; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in San Antonio, TX

Summer high97 °Faverage high, August
Winter low41 °Faverage low, January
Hot days141days a year at 90 °F or more
Freezing nights14nights a year at 32 °F or less
Growing degree days7,412base 50 °F — the season’s usable heat
Longest day14 h 02 mindaylight on June 21
Shortest day10 h 15 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation34 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 64 °F, low 41 °F 64°41° JanFebruary: average high 70 °F, low 44 °F 70°44° FebMarch: average high 75 °F, low 52 °F 75°52° MarApril: average high 82 °F, low 59 °F 82°59° AprMay: average high 89 °F, low 66 °F 89°66° MayJune: average high 93 °F, low 72 °F 93°72° JunJuly: average high 96 °F, low 74 °F 96°74° JulAugust: average high 97 °F, low 74 °F 97°74° AugSeptember: average high 92 °F, low 70 °F 92°70° SepOctober: average high 84 °F, low 60 °F 84°60° OctNovember: average high 72 °F, low 49 °F 72°49° NovDecember: average high 65 °F, low 41 °F 65°41° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.21 in precipitation 2.2 JanFebruary: 1.87 in precipitation 1.9 FebMarch: 2.38 in precipitation 2.4 MarApril: 2.32 in precipitation 2.3 AprMay: 4.38 in precipitation 4.4 MayJune: 3.55 in precipitation 3.5 JunJuly: 2.41 in precipitation 2.4 JulAugust: 2.43 in precipitation 2.4 AugSeptember: 3.90 in precipitation 3.9 SepOctober: 3.93 in precipitation 3.9 OctNovember: 2.48 in precipitation 2.5 NovDecember: 2.11 in precipitation, 0.1 in snowfall 2.1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: San Antonio Kelly AFB, TX (4 mi away); precipitation: San Antonio Incarnate Word, TX (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9a.

782049a
San Antonio, TX · 2 mi
782889a
San Antonio, TX · 2 mi
782259a
San Antonio, TX · 2 mi
782059a
San Antonio, TX · 2 mi
782379a
San Antonio, TX · 2 mi
782849a
San Antonio, TX · 3 mi
782159a
San Antonio, TX · 3 mi
782019a
San Antonio, TX · 3 mi

All 82 ZIP codes in San Antonio → · Texas planting zones →

Questions about 78207

What planting zone is ZIP code 78207?

ZIP code 78207 (San Antonio, TX) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in San Antonio, TX?

The median last spring frost (32 °F) near 78207 is February 22; after March 12 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, San Antonio Kelly AFB station.

When is the first frost in San Antonio, TX?

The median first fall frost near 78207 is December 2, giving a median frost-free growing season of 284 days.

When should I plant tomatoes in 78207?

Start tomato seeds indoors around Dec 28 – Jan 11 and set transplants outside around Mar 1 – Mar 15, one to three weeks after the median last frost.

How much rain and snow does 78207 get?

About 34 inches of precipitation a year (NOAA 1991–2020 normals, San Antonio Incarnate Word station).

How hot do summers get in San Antonio, TX?

The average high peaks at 97 °F in August, with about 141 days a year at 90 °F or more.

What kind of soil does 78207 have?

The USDA soil survey maps Lewisville at the center of ZIP 78207: silty clay, well drained, pH about 8.2 (alkaline).

Did spring come early in San Antonio, TX in 2026?

Spring leaf-out near 78207 came on Jan 20 in 2026, 4 days earlier than the 1991–2020 average (Jan 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in San Antonio, TX?

Short-day onions: the longest day near 78207 is 14 h 02 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.