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

Planting zone for 75426 — Clarksville, TX

ZIP code 75426 (Clarksville, Red River County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 20 and the first fall frost November 10.

Where ZIP 75426 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 frostMar 20

First frostNov 10

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 Clarksville, 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 Clarksville, TX

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 20median — 50% chance of a later frost

Safe for tender plantsApril 11only 10% chance of frost after

First fall frostNovember 10median — 10% chance by Oct 28

Growing season233 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 5 and returns around November 23.

From the NOAA station Clarksville 2ne, TX — 4 miles away, elevation 436 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 75426

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 6 – Feb 20

SpinachSow outdoors · Feb 6 – Feb 27

Broccoli, cabbageStart indoors · Jan 9 – Jan 23

Broccoli, cabbageTransplant · Feb 27 – Mar 13

Onion setsPlant outdoors · Feb 20 – Mar 6

PotatoesPlant outdoors · Feb 27 – Mar 13

LettuceSow outdoors · Feb 20 – Mar 6

Carrots, beetsSow outdoors · Feb 27 – Mar 13

TomatoesStart indoors · Jan 23 – Feb 6

TomatoesTransplant · Mar 27 – Apr 10

Peppers, eggplantStart indoors · Jan 9 – Jan 23

Peppers, eggplantTransplant · Apr 3 – Apr 17

BeansSow outdoors · Mar 27 – Apr 10

Sweet cornSow outdoors · Mar 27 – Apr 10

Cucumbers, squashSow outdoors · Mar 27 – Apr 10

Fall lettuce, spinachSow outdoors · Sep 15 – Sep 29

GarlicPlant cloves · Oct 27 – Dec 1

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 20) and first fall frost (Nov 10) 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 75426 came on Feb 10 — about the same time as the 1991–2020 average (Feb 11).

average
Feb 112026
Feb 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 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 Clarksville, TX.

Soil in Clarksville, TX

The soil mapped at the center of ZIP 75426 is Ferris — clay, well drained.

TextureClayholds water and nutrients; slow to drain and warm up

pH8.2alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Ferris clay, 3 to 8 percent slopes eroded.

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 75426; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Clarksville, TX

Summer high93 °Faverage high, August

Winter low32 °Faverage low, January

Hot days72days a year at 90 °F or more

Freezing nights57nights a year at 32 °F or less

Growing degree days5,547base 50 °F — the season’s usable heat

Longest day14 h 23 mindaylight on June 21

Shortest day9 h 55 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation49.4 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: Clarksville 2ne, TX (4 mi away); precipitation: Clarksville 2ne, TX (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

2 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

Texas planting zones →

Questions about 75426

What planting zone is ZIP code 75426?

ZIP code 75426 (Clarksville, 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 Clarksville, TX?

The median last spring frost (32 °F) near 75426 is March 20; after April 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Clarksville 2ne station.

When is the first frost in Clarksville, TX?

The median first fall frost near 75426 is November 10, giving a median frost-free growing season of 233 days.

When should I plant tomatoes in 75426?

Start tomato seeds indoors around Jan 23 – Feb 6 and set transplants outside around Mar 27 – Apr 10, one to three weeks after the median last frost.

How much rain and snow does 75426 get?

About 49.4 inches of precipitation a year (NOAA 1991–2020 normals, Clarksville 2ne station).

How hot do summers get in Clarksville, TX?

The average high peaks at 93 °F in August, with about 72 days a year at 90 °F or more.

What kind of soil does 75426 have?

The USDA soil survey maps Ferris at the center of ZIP 75426: clay, well drained, pH about 8.2 (alkaline).

Did spring come early in Clarksville, TX in 2026?

Spring leaf-out near 75426 came on Feb 10 in 2026, about the same as the 1991–2020 average (Feb 11), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Clarksville, TX?

Intermediate onions: the longest day near 75426 is 14 h 23 min, so day-neutral types bulb best; long-day varieties may not bulb fully.