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

Planting zone for 76641 — Frost, TX

ZIP code 76641 (Frost, Navarro County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 13 and the first fall frost November 14.

Where ZIP 76641 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.

Zone8b15 to 20 °F

Coldest night−9.4 to −6.7 °C

Last frostMar 13

First frostNov 14

2012 zone8a

Was 8a 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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Frost, 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 Frost, TX

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 13median — 50% chance of a later frost

Safe for tender plantsApril 3only 10% chance of frost after

First fall frostNovember 14median — 10% chance by Oct 30

Growing season250 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 27 and returns around November 29.

From the NOAA station Navarro Mills Dam, TX — 8 miles away, elevation 453 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 76641

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 30 – Feb 13

SpinachSow outdoors · Jan 30 – Feb 20

Broccoli, cabbageStart indoors · Jan 2 – Jan 16

Broccoli, cabbageTransplant · Feb 20 – Mar 6

Onion setsPlant outdoors · Feb 13 – Feb 27

PotatoesPlant outdoors · Feb 20 – Mar 6

LettuceSow outdoors · Feb 13 – Feb 27

Carrots, beetsSow outdoors · Feb 20 – Mar 6

TomatoesStart indoors · Jan 16 – Jan 30

TomatoesTransplant · Mar 20 – Apr 3

Peppers, eggplantStart indoors · Jan 2 – Jan 16

Peppers, eggplantTransplant · Mar 27 – Apr 10

BeansSow outdoors · Mar 20 – Apr 3

Sweet cornSow outdoors · Mar 20 – Apr 3

Cucumbers, squashSow outdoors · Mar 20 – Apr 3

Fall lettuce, spinachSow outdoors · Sep 19 – Oct 3

GarlicPlant cloves · Oct 31 – Dec 5

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 13) and first fall frost (Nov 14) 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 76641 came on Feb 7 — 4 days later than the 1991–2020 average (Feb 3).

average
Feb 32026
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).

Soil in Frost, TX

The soil mapped at the center of ZIP 76641 is Houston Black — clay, moderately well drained.

TextureClayholds water and nutrients; slow to drain and warm up

pH7.9alkaline; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter3%moderate

Hydrologic groupDwater soaks in very slowly

Farmland classprime farmlandUSDA classification

Map unit: Houston Black 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 76641; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Frost, TX

Summer high96 °Faverage high, August

Winter low35 °Faverage low, January

Hot days109days a year at 90 °F or more

Freezing nights44nights a year at 32 °F or less

Growing degree days6,362base 50 °F — the season’s usable heat

Longest day14 h 15 mindaylight on June 21

Shortest day10 h 03 mindaylight on December 21

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

Precipitation40.5 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: Navarro Mills Dam, TX (8 mi away); precipitation: Navarro Mills Dam, TX (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

Blooming Grove, TX · 7 mi

Texas planting zones →

Questions about 76641

What planting zone is ZIP code 76641?

ZIP code 76641 (Frost, TX) is in USDA hardiness zone 8b on the 2023 map: the coldest night of an average winter reaches 15 to 20 °F (−9.4 to −6.7 °C).

When is the last frost in Frost, TX?

The median last spring frost (32 °F) near 76641 is March 13; after April 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Navarro Mills Dam station.

When is the first frost in Frost, TX?

The median first fall frost near 76641 is November 14, giving a median frost-free growing season of 250 days.

When should I plant tomatoes in 76641?

Start tomato seeds indoors around Jan 16 – Jan 30 and set transplants outside around Mar 20 – Apr 3, one to three weeks after the median last frost.

How much rain and snow does 76641 get?

About 40.5 inches of precipitation a year (NOAA 1991–2020 normals, Navarro Mills Dam station).

How hot do summers get in Frost, TX?

The average high peaks at 96 °F in August, with about 109 days a year at 90 °F or more.

What kind of soil does 76641 have?

The USDA soil survey maps Houston Black at the center of ZIP 76641: clay, moderately well drained, pH about 7.9 (alkaline).

Did spring come early in Frost, TX in 2026?

Spring leaf-out near 76641 came on Feb 7 in 2026, 4 days later than the 1991–2020 average (Feb 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Frost, TX?

Short-day onions: the longest day near 76641 is 14 h 15 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 76641 change?

Yes. The 2012 USDA map put 76641 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.