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

Planting zone for 71638 — Dermott, AR

ZIP code 71638 (Dermott, Chicot 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 10.

Where ZIP 71638 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 10

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 Dermott, AR…

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 Dermott, AR

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 plantsMarch 31only 10% chance of frost after

First fall frostNovember 10median — 10% chance by Oct 25

Growing season242 daysfrost-free, median

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

From the NOAA station Dermott 3 Ne, AR — 6 miles away, elevation 144 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 71638

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 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 13) 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 71638 came on Feb 12 — 3 days later than the 1991–2020 average (Feb 9).

average
Feb 92026
Feb 12

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 8b in Arkansas

521 plants native to the lower 48 states, recorded in Arkansas, and rated by the USDA to survive 15 °F or colder — the bottom of zone 8b. 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 Dermott, AR.

Soil in Dermott, AR

The soil mapped at the center of ZIP 71638 is Perry — clay, poorly drained.

TextureClayholds water and nutrients; slow to drain and warm up

pH5.3strongly acidic; most vegetables like 6.0–7.0

DrainagePoorly drainedconsider raised beds

Organic matter2.25%moderate

Hydrologic groupDwater soaks in very slowly

Farmland classPrime farmland if drainedUSDA classification

Map unit: Perry clay, 0 to 1 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 71638; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Dermott, AR

Summer high91 °Faverage high, July

Winter low34 °Faverage low, January

Hot days86days a year at 90 °F or more

Freezing nights47nights a year at 32 °F or less

Growing degree days5,601base 50 °F — the season’s usable heat

Longest day14 h 23 mindaylight on June 21

Shortest day9 h 56 mindaylight on December 21

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

Precipitation56.3 inper year, rain and melted snow

Snowfall1 inper year

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Dermott 3 Ne, AR (6 mi away); precipitation: Dermott 3 Ne, AR (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

Lake Village, AR · 16 mi

716308b

Arkansas City, AR · 16 mi

716558b

Monticello, AR · 16 mi

716708b

Tillar, AR · 16 mi

716778b

Winchester, AR · 17 mi

716668b

Rohwer, AR · 20 mi

Arkansas planting zones →

Questions about 71638

What planting zone is ZIP code 71638?

ZIP code 71638 (Dermott, AR) 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 Dermott, AR?

The median last spring frost (32 °F) near 71638 is March 13; after March 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Dermott 3 Ne station.

When is the first frost in Dermott, AR?

The median first fall frost near 71638 is November 10, giving a median frost-free growing season of 242 days.

When should I plant tomatoes in 71638?

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 71638 get?

About 56.3 inches of precipitation a year and 1 inches of snowfall (NOAA 1991–2020 normals, Dermott 3 Ne station).

How hot do summers get in Dermott, AR?

The average high peaks at 91 °F in July, with about 86 days a year at 90 °F or more.

What kind of soil does 71638 have?

The USDA soil survey maps Perry at the center of ZIP 71638: clay, poorly drained, pH about 5.3 (strongly acidic).

Did spring come early in Dermott, AR in 2026?

Spring leaf-out near 71638 came on Feb 12 in 2026, 3 days later than the 1991–2020 average (Feb 9), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Dermott, AR?

Intermediate onions: the longest day near 71638 is 14 h 23 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 71638 change?

Yes. The 2012 USDA map put 71638 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.