USDA zone 6b in Texas

−5 to 0 °F avg. annual extreme minimum · 5 locations in this group · NOAA 1991–2020 normals

USDA plant hardiness zone 6b covers 5 locations across Texas (average annual extreme minimum −5 to 0 °F): Dalhart, TX, Lipscomb, TX, Perryton, TX, Stratford, TX, Texhoma, TX. Average last spring frost across this group ranges April 14 (Perryton) to April 27 (Lipscomb), and growing seasons run 170–197 days (Lipscomb to Perryton) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Texas location's own frost dates; the printable planting calendar uses Dalhart, this group's median-season location.

USDA zone
6b−5 to 0 °F
Last frost range
Apr 14–Apr 27avg, 32°F
First frost range
Oct 15–Oct 30avg, 32°F
Growing season range
170–197days

Locations in this group

Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.

Own frost dates per location.
LocationAlso coversNearest stationLast frostFirst frostSeason (days)
Dalhart *Dalhart Muni ApApr 21Oct 20181
LipscombLipscombApr 27Oct 15170
PerrytonPerrytonApr 14Oct 30197
StratfordTexhomaStratfordApr 21Oct 21181
TexhomaHoughGoodwell Rsch StnApr 24Oct 19178

* Dalhart is this group's median-season location — the calendar below is computed from its data.

Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.

Planting calendar (Dalhart, representative)

Computed from Dalhart's average frost dates — the median-season location in this Texaszone 6b group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).

  • Start indoors
  • Plant out
  • Fall sowing
  • First harvest
Planting windows for Dalhart (Texas, zone 6b), this group's representative location.
CropFrost toleranceStart indoorsPlant outFirst harvestFall plantingSeason fit
TomatoTenderFeb 24 – Mar 10Apr 28 – May 5Jun 27 – Jul 17matures comfortably
PepperVery tenderFeb 10 – Feb 24May 5 – May 12Jul 4 – Aug 3matures comfortably
CucumberTenderMar 24 – Mar 31Apr 28 – May 5Jun 17 – Jul 7matures comfortably
Summer squash / zucchiniTenderApr 28 – May 5Jun 12 – Jun 27matures comfortably
Bush beanTenderApr 28 – May 5Jun 17 – Jun 27Aug 21 – Aug 31matures comfortably
Sweet cornTenderApr 21 – May 5Jun 20 – Jul 20matures comfortably
BasilVery tenderMar 10 – Mar 24Apr 28 – May 5May 28 – Jun 12matures comfortably
LettuceHalf-hardyMar 10 – Mar 24Mar 24 – Apr 7May 8 – May 23Aug 7 – Aug 22matures comfortably
PeaHardyMar 10 – Mar 24May 4 – May 19Jul 28 – Aug 12matures comfortably
SpinachHardyMar 10 – Mar 24Apr 19 – Apr 29Aug 17 – Aug 27matures comfortably
CarrotHalf-hardyMar 31 – Apr 7May 30 – Jun 19Jul 18 – Aug 7matures comfortably
BroccoliHalf-hardyFeb 24 – Mar 10Mar 24 – Apr 7May 18 – Jun 7Jul 23 – Aug 12matures comfortably

Which crops fit this growing season

Using Dalhart's own 181-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.

Frost & freeze dates (Dalhart)

From NOAA's 1991–2020 Climate Normals at station USW00093042. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020), Dalhart.
ThresholdLast spring — avgLast spring — 90%-safeFirst fall — avgFirst fall — 90%-safeSeason (days)
36°FMay 1May 13Oct 12Oct 22162
32°F (freeze)Apr 21May 4Oct 20Nov 1181
28°FApr 10Apr 25Oct 29Nov 10200
24°FMar 30Apr 13Nov 7Nov 20221

Growing degree days

Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 5 locations is 4,129; Dalhart's own reading is shown below.

Annual growing degree days for Dalhart (°F·days, NOAA 1991–2020).
Model°F·daysUsed for
Base 50°F (warm-season)4,129standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season)6,736cool-season crops (brassicas, greens)

Hardiness zone 6b in Texas

Zone 6b means an average annual extreme minimum winter temperature of about −5 to 0 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Texas spans 9 hardiness zones in this dataset — see all Texas locations for the full range, including zones7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b.

Explore zone 6b in other states at zone 6b, or see all USDA hardiness zones.

Frequently asked questions

What does USDA hardiness zone 6b mean in Texas?
Zone 6b means an average annual extreme minimum winter temperature of −5 to 0 °F — the standard USDA measure of which perennials survive winter. 5 locations in Texas fall in this zone. It does not set planting dates; see the frost calendar below for that.
Where in Texas's zone 6b is the growing season longest?
Perryton runs the longest season on this page at about 197 days; Lipscomb is shortest at about 170 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
When should I plant tomatoes in Texas's zone 6b?
Using Dalhart's frost dates (this page's median-season location): start seeds indoors about Feb 24 – Mar 10, then transplant outside about Apr 28 – May 5. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
Does every location in Texas's zone 6b have the same frost dates?
No — they do not all share a weather station, so frost dates vary by a week or more across the 5 locations listed (see the table above for each location's own dates).

Sources & method

Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.