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

Planting zone for 78371 — Oilton, TX

ZIP code 78371 (Oilton, Webb County) is in USDA zone 9b: the coldest winter night averages 25 to 30 °F. The median last spring frost is January 30 and the first fall frost December 18.

Where ZIP 78371 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.

Zone9b25 to 30 °F

Coldest night−3.9 to −1.1 °C

Last frostJan 30

First frostDec 18

2012 zone9a

Was 9a 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 9b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Oilton, 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 Oilton, TX

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostJanuary 30median — 50% chance of a later frost

Safe for tender plantsMarch 1only 10% chance of frost after

First fall frostDecember 18median — 10% chance by Nov 22

Growing season323 daysfrost-free, median

A hard freeze (28 °F) usually ends around January 11 and returns around January 1.

From the NOAA station Bruni, TX — 16 miles away, elevation 771 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 78371

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Dec 19 – Jan 2

SpinachSow outdoors · Dec 19 – Jan 9

Broccoli, cabbageStart indoors · Nov 21 – Dec 5

Broccoli, cabbageTransplant · Jan 9 – Jan 23

Onion setsPlant outdoors · Jan 2 – Jan 16

PotatoesPlant outdoors · Jan 9 – Jan 23

LettuceSow outdoors · Jan 2 – Jan 16

Carrots, beetsSow outdoors · Jan 9 – Jan 23

TomatoesStart indoors · Dec 5 – Dec 19

TomatoesTransplant · Feb 6 – Feb 20

Peppers, eggplantStart indoors · Nov 21 – Dec 5

Peppers, eggplantTransplant · Feb 13 – Feb 27

BeansSow outdoors · Feb 6 – Feb 20

Sweet cornSow outdoors · Feb 6 – Feb 20

Cucumbers, squashSow outdoors · Feb 6 – Feb 20

Fall lettuce, spinachSow outdoors · Oct 23 – Nov 6

GarlicPlant cloves · Dec 4 – Jan 8

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jan 30) and first fall frost (Dec 18) 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 78371 came on Jan 10 — 10 days earlier than the 1991–2020 average (Jan 20).

average
Jan 202026
Jan 10

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 9b in Texas

646 plants native to the lower 48 states, recorded in Texas, and rated by the USDA to survive 25 °F or colder — the bottom of zone 9b. 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 Oilton, TX.

Soil in Oilton, TX

The soil mapped at the center of ZIP 78371 is Aguilares — sandy clay loam, well drained.

TextureSandy clay loamholds water and nutrients; slow to drain and warm up

pH8.0alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Aguilares sandy clay loam, 0 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 78371; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Oilton, TX

Summer high99 °Faverage high, August

Winter low44 °Faverage low, January

Hot days160days a year at 90 °F or more

Freezing nights5nights a year at 32 °F or less

Growing degree days8,318base 50 °F — the season’s usable heat

Longest day13 h 53 mindaylight on June 21

Shortest day10 h 24 mindaylight on December 21

Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb

Precipitation25.7 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: Bruni, TX (16 mi away); precipitation: Bruni, TX (16 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9b.

783699b

Mirando City, TX · 6 mi

Texas planting zones →

Questions about 78371

What planting zone is ZIP code 78371?

ZIP code 78371 (Oilton, TX) is in USDA hardiness zone 9b on the 2023 map: the coldest night of an average winter reaches 25 to 30 °F (−3.9 to −1.1 °C).

When is the last frost in Oilton, TX?

The median last spring frost (32 °F) near 78371 is January 30; after March 1 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bruni station.

When is the first frost in Oilton, TX?

The median first fall frost near 78371 is December 18, giving a median frost-free growing season of 323 days.

When should I plant tomatoes in 78371?

Start tomato seeds indoors around Dec 5 – Dec 19 and set transplants outside around Feb 6 – Feb 20, one to three weeks after the median last frost.

How much rain and snow does 78371 get?

About 25.7 inches of precipitation a year (NOAA 1991–2020 normals, Bruni station).

How hot do summers get in Oilton, TX?

The average high peaks at 99 °F in August, with about 160 days a year at 90 °F or more.

What kind of soil does 78371 have?

The USDA soil survey maps Aguilares at the center of ZIP 78371: sandy clay loam, well drained, pH about 8.0 (alkaline).

Did spring come early in Oilton, TX in 2026?

Spring leaf-out near 78371 came on Jan 10 in 2026, 10 days earlier than the 1991–2020 average (Jan 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Oilton, TX?

Short-day onions: the longest day near 78371 is 13 h 53 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 78371 change?

Yes. The 2012 USDA map put 78371 in zone 9a; the 2023 map puts it in zone 9b. The newer map uses 1991–2020 data and more weather stations.