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

Planting zone for 76941 — Mertzon, TX

ZIP code 76941 (Mertzon, Irion County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is April 1 and the first fall frost November 4.

Where ZIP 76941 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.

Zone8a10 to 15 °F

Coldest night−12.2 to −9.4 °C

Last frostApr 1

First frostNov 4

2012 zone8a

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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mertzon, 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 Mertzon, TX

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 1median — 50% chance of a later frost

Safe for tender plantsApril 19only 10% chance of frost after

First fall frostNovember 4median — 10% chance by Oct 21

Growing season215 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 19 and returns around November 12.

From the NOAA station Mertzon 12nnw, TX — 13 miles away, elevation 2,205 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 76941

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 18 – Mar 4

SpinachSow outdoors · Feb 18 – Mar 11

Broccoli, cabbageStart indoors · Jan 21 – Feb 4

Broccoli, cabbageTransplant · Mar 11 – Mar 25

Onion setsPlant outdoors · Mar 4 – Mar 18

PotatoesPlant outdoors · Mar 11 – Mar 25

LettuceSow outdoors · Mar 4 – Mar 18

Carrots, beetsSow outdoors · Mar 11 – Mar 25

TomatoesStart indoors · Feb 4 – Feb 18

TomatoesTransplant · Apr 8 – Apr 22

Peppers, eggplantStart indoors · Jan 21 – Feb 4

Peppers, eggplantTransplant · Apr 15 – Apr 29

BeansSow outdoors · Apr 8 – Apr 22

Sweet cornSow outdoors · Apr 8 – Apr 22

Cucumbers, squashSow outdoors · Apr 8 – Apr 22

Fall lettuce, spinachSow outdoors · Sep 9 – Sep 23

GarlicPlant cloves · Oct 21 – Nov 25

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 1) and first fall frost (Nov 4) 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 76941 came on Feb 7 — about the same time as the 1991–2020 average (Feb 5).

average
Feb 52026
Feb 7

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 8a in Texas

601 plants native to the lower 48 states, recorded in Texas, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. 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 Mertzon, TX.

Soil in Mertzon, TX

The soil mapped at the center of ZIP 76941 is Ector — very gravelly loam, well drained.

TextureVery gravelly loama good balance for most vegetables

pH8.0alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter7%high

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Ector soils, moist, 1 to 8 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 76941; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mertzon, TX

Summer high95 °Faverage high, August

Winter low29 °Faverage low, January

Hot days116days a year at 90 °F or more

Freezing nights74nights a year at 32 °F or less

Growing degree days5,829base 50 °F — the season’s usable heat

Longest day14 h 11 mindaylight on June 21

Shortest day10 h 07 mindaylight on December 21

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

Precipitation23.8 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: Mertzon 12nnw, TX (13 mi away); precipitation: Knickerbocker 3.2 Sw, TX (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8a.

769398a

Knickerbocker, TX · 16 mi

769308a

Barnhart, TX · 18 mi

769018a

San Angelo, TX · 22 mi

769028a

San Angelo, TX · 22 mi

769048a

San Angelo, TX · 26 mi

769098a

San Angelo, TX · 27 mi

Texas planting zones →

Questions about 76941

What planting zone is ZIP code 76941?

ZIP code 76941 (Mertzon, TX) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Mertzon, TX?

The median last spring frost (32 °F) near 76941 is April 1; after April 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mertzon 12nnw station.

When is the first frost in Mertzon, TX?

The median first fall frost near 76941 is November 4, giving a median frost-free growing season of 215 days.

When should I plant tomatoes in 76941?

Start tomato seeds indoors around Feb 4 – Feb 18 and set transplants outside around Apr 8 – Apr 22, one to three weeks after the median last frost.

How much rain and snow does 76941 get?

About 23.8 inches of precipitation a year (NOAA 1991–2020 normals, Knickerbocker 3.2 Sw station).

How hot do summers get in Mertzon, TX?

The average high peaks at 95 °F in August, with about 116 days a year at 90 °F or more.

What kind of soil does 76941 have?

The USDA soil survey maps Ector at the center of ZIP 76941: very gravelly loam, well drained, pH about 8.0 (alkaline).

Did spring come early in Mertzon, TX in 2026?

Spring leaf-out near 76941 came on Feb 7 in 2026, about the same as the 1991–2020 average (Feb 5), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mertzon, TX?

Short-day onions: the longest day near 76941 is 14 h 11 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.