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

Planting zone for 78748 — Austin, TX

ZIP code 78748 (Austin, Travis County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is March 10 and the first fall frost November 17.

Where ZIP 78748 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 frostMar 10
First frostNov 17
2012 zone8b

Was 8b on the 2012 map — half a zone warmer now. 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 Austin, 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 Austin, TX

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 10median — 50% chance of a later frost
Safe for tender plantsMarch 31only 10% chance of frost after
First fall frostNovember 17median — 10% chance by Nov 1
Growing season252 daysfrost-free, median

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

From the NOAA station Austin 6s, TX — 7 miles away, elevation 571 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 78748

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 27 – Feb 10
SpinachSow outdoors · Jan 27 – Feb 17
Broccoli, cabbageStart indoors · Dec 30 – Jan 13
Broccoli, cabbageTransplant · Feb 17 – Mar 3
Onion setsPlant outdoors · Feb 10 – Feb 24
PotatoesPlant outdoors · Feb 17 – Mar 3
LettuceSow outdoors · Feb 10 – Feb 24
Carrots, beetsSow outdoors · Feb 17 – Mar 3
TomatoesStart indoors · Jan 13 – Jan 27
TomatoesTransplant · Mar 17 – Mar 31
Peppers, eggplantStart indoors · Dec 30 – Jan 13
Peppers, eggplantTransplant · Mar 24 – Apr 7
BeansSow outdoors · Mar 17 – Mar 31
Sweet cornSow outdoors · Mar 17 – Mar 31
Cucumbers, squashSow outdoors · Mar 17 – Mar 31
Fall lettuce, spinachSow outdoors · Sep 22 – Oct 6
GarlicPlant cloves · Nov 3 – Dec 8
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 10) and first fall frost (Nov 17) 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 78748 came on Jan 29 — about the same time as the 1991–2020 average (Jan 27).

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).

Native plants for zone 9a in Texas

640 plants native to the lower 48 states, recorded in Texas, and rated by the USDA to survive 20 °F or colder — the bottom of zone 9a. Each links to its USDA PLANTS profile.

Trees 72

Shrubs 141

Wildflowers & perennials 208

Grasses 196

Vines 14

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Austin, TX.

Soil in Austin, TX

The soil mapped at the center of ZIP 78748 is Crawford — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up
pH7.3neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classprime farmlandUSDA classification

Map unit: Crawford 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 78748; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Austin, TX

Summer high97 °Faverage high, August
Winter low37 °Faverage low, January
Hot days121days a year at 90 °F or more
Freezing nights29nights a year at 32 °F or less
Growing degree days6,708base 50 °F — the season’s usable heat
Longest day14 h 05 mindaylight on June 21
Shortest day10 h 12 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation39 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 59 °F, low 37 °F 59°37° JanFebruary: average high 64 °F, low 41 °F 64°41° FebMarch: average high 73 °F, low 48 °F 73°48° MarApril: average high 79 °F, low 54 °F 79°54° AprMay: average high 86 °F, low 63 °F 86°63° MayJune: average high 93 °F, low 70 °F 93°70° JunJuly: average high 96 °F, low 72 °F 96°72° JulAugust: average high 97 °F, low 72 °F 97°72° AugSeptember: average high 91 °F, low 66 °F 91°66° SepOctober: average high 81 °F, low 55 °F 81°55° OctNovember: average high 71 °F, low 46 °F 71°46° NovDecember: average high 63 °F, low 39 °F 63°39° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 2.80 in precipitation 2.8 JanFebruary: 2.01 in precipitation 2.0 FebMarch: 3.01 in precipitation 3.0 MarApril: 2.67 in precipitation 2.7 AprMay: 5.37 in precipitation 5.4 MayJune: 4.21 in precipitation 4.2 JunJuly: 2.40 in precipitation 2.4 JulAugust: 2.82 in precipitation 2.8 AugSeptember: 3.69 in precipitation 3.7 SepOctober: 4.23 in precipitation 4.2 OctNovember: 3.00 in precipitation 3.0 NovDecember: 2.76 in precipitation 2.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Austin 6s, TX (7 mi away); precipitation: Tanglewood Forest 2.9 E, TX (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9a.

All 73 ZIP codes in Austin → · Texas planting zones →

Questions about 78748

What planting zone is ZIP code 78748?

ZIP code 78748 (Austin, 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 Austin, TX?

The median last spring frost (32 °F) near 78748 is March 10; after March 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Austin 6s station.

When is the first frost in Austin, TX?

The median first fall frost near 78748 is November 17, giving a median frost-free growing season of 252 days.

When should I plant tomatoes in 78748?

Start tomato seeds indoors around Jan 13 – Jan 27 and set transplants outside around Mar 17 – Mar 31, one to three weeks after the median last frost.

How much rain and snow does 78748 get?

About 39 inches of precipitation a year (NOAA 1991–2020 normals, Tanglewood Forest 2.9 E station).

How hot do summers get in Austin, TX?

The average high peaks at 97 °F in August, with about 121 days a year at 90 °F or more.

What kind of soil does 78748 have?

The USDA soil survey maps Crawford at the center of ZIP 78748: clay, well drained, pH about 7.3 (neutral).

Did spring come early in Austin, TX in 2026?

Spring leaf-out near 78748 came on Jan 29 in 2026, about the same as the 1991–2020 average (Jan 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Austin, TX?

Short-day onions: the longest day near 78748 is 14 h 05 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 78748 change?

Yes. The 2012 USDA map put 78748 in zone 8b; the 2023 map puts it in zone 9a. The newer map uses 1991–2020 data and more weather stations.