Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 78614 — Cost, TX

ZIP code 78614 (Cost, Gonzales County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 26 and the first fall frost November 28.

Where ZIP 78614 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 26

First frostNov 28

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 Cost, 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 Cost, TX

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostFebruary 26median — 50% chance of a later frost

Safe for tender plantsMarch 21only 10% chance of frost after

First fall frostNovember 28median — 10% chance by Nov 7

Growing season272 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 6 and returns around December 12.

From the NOAA station Gonzales 2s, TX — 9 miles away, elevation 295 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 78614

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 15 – Jan 29

SpinachSow outdoors · Jan 15 – Feb 5

Broccoli, cabbageStart indoors · Dec 18 – Jan 1

Broccoli, cabbageTransplant · Feb 5 – Feb 19

Onion setsPlant outdoors · Jan 29 – Feb 12

PotatoesPlant outdoors · Feb 5 – Feb 19

LettuceSow outdoors · Jan 29 – Feb 12

Carrots, beetsSow outdoors · Feb 5 – Feb 19

TomatoesStart indoors · Jan 1 – Jan 15

TomatoesTransplant · Mar 5 – Mar 19

Peppers, eggplantStart indoors · Dec 18 – Jan 1

Peppers, eggplantTransplant · Mar 12 – Mar 26

BeansSow outdoors · Mar 5 – Mar 19

Sweet cornSow outdoors · Mar 5 – Mar 19

Cucumbers, squashSow outdoors · Mar 5 – Mar 19

Fall lettuce, spinachSow outdoors · Oct 3 – Oct 17

GarlicPlant cloves · Nov 14 – Dec 19

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 26) and first fall frost (Nov 28) 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 78614 came on Jan 15 — 10 days earlier than the 1991–2020 average (Jan 25).

average
Jan 252026
Jan 15

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.

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 Cost, TX.

Soil in Cost, TX

The soil mapped at the center of ZIP 78614 is Luling — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up

pH7.5slightly alkaline; 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: Luling clay, 1 to 3 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 78614; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cost, TX

Summer high96 °Faverage high, August

Winter low40 °Faverage low, January

Hot days113days a year at 90 °F or more

Freezing nights19nights a year at 32 °F or less

Growing degree days7,170base 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

Precipitation34.2 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Gonzales 2s, TX (9 mi away); precipitation: Gonzales 10 Sw, TX (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9a.

786779a

Wrightsboro, TX · 4 mi

Texas planting zones →

Questions about 78614

What planting zone is ZIP code 78614?

ZIP code 78614 (Cost, 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 Cost, TX?

The median last spring frost (32 °F) near 78614 is February 26; after March 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Gonzales 2s station.

When is the first frost in Cost, TX?

The median first fall frost near 78614 is November 28, giving a median frost-free growing season of 272 days.

When should I plant tomatoes in 78614?

Start tomato seeds indoors around Jan 1 – Jan 15 and set transplants outside around Mar 5 – Mar 19, one to three weeks after the median last frost.

How much rain and snow does 78614 get?

About 34.2 inches of precipitation a year (NOAA 1991–2020 normals, Gonzales 10 Sw station).

How hot do summers get in Cost, TX?

The average high peaks at 96 °F in August, with about 113 days a year at 90 °F or more.

What kind of soil does 78614 have?

The USDA soil survey maps Luling at the center of ZIP 78614: clay, well drained, pH about 7.5 (slightly alkaline).

Did spring come early in Cost, TX in 2026?

Spring leaf-out near 78614 came on Jan 15 in 2026, 10 days earlier than the 1991–2020 average (Jan 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cost, TX?

Short-day onions: the longest day near 78614 is 14 h 02 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 78614 change?

Yes. The 2012 USDA map put 78614 in zone 8b; the 2023 map puts it in zone 9a. The newer map uses 1991–2020 data and more weather stations.