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

Planting zone for 72821 — Altus, AR

ZIP code 72821 (Altus, Franklin County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 30 and the first fall frost November 6.

Where ZIP 72821 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 30

First frostNov 6

2012 zone7b

Was 7b 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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Altus, 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 Altus, AR

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 30median — 50% chance of a later frost

Safe for tender plantsApril 17only 10% chance of frost after

First fall frostNovember 6median — 10% chance by Oct 23

Growing season222 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 15 and returns around November 18.

From the NOAA station Ozark 2, AR — 9 miles away, elevation 830 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 72821

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 16 – Mar 2

SpinachSow outdoors · Feb 16 – Mar 9

Broccoli, cabbageStart indoors · Jan 19 – Feb 2

Broccoli, cabbageTransplant · Mar 9 – Mar 23

Onion setsPlant outdoors · Mar 2 – Mar 16

PotatoesPlant outdoors · Mar 9 – Mar 23

LettuceSow outdoors · Mar 2 – Mar 16

Carrots, beetsSow outdoors · Mar 9 – Mar 23

TomatoesStart indoors · Feb 2 – Feb 16

TomatoesTransplant · Apr 6 – Apr 20

Peppers, eggplantStart indoors · Jan 19 – Feb 2

Peppers, eggplantTransplant · Apr 13 – Apr 27

BeansSow outdoors · Apr 6 – Apr 20

Sweet cornSow outdoors · Apr 6 – Apr 20

Cucumbers, squashSow outdoors · Apr 6 – Apr 20

Fall lettuce, spinachSow outdoors · Sep 11 – Sep 25

GarlicPlant cloves · Oct 23 – Nov 27

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 30) and first fall frost (Nov 6) 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 72821 came on Feb 13 — 11 days earlier than the 1991–2020 average (Feb 24).

average
Feb 242026
Feb 13

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 Arkansas

516 plants native to the lower 48 states, recorded in Arkansas, 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 Altus, AR.

Soil in Altus, AR

The soil mapped at the center of ZIP 72821 is Linker — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding

pH5.6moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.75%low — add compost

Hydrologic groupCwater soaks in slowly

Farmland classprime farmlandUSDA classification

Map unit: Linker fine sandy loam, 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 72821; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Altus, AR

Summer high92 °Faverage high, July

Winter low28 °Faverage low, January

Hot days62days a year at 90 °F or more

Freezing nights72nights a year at 32 °F or less

Growing degree days4,930base 50 °F — the season’s usable heat

Longest day14 h 33 mindaylight on June 21

Shortest day9 h 45 mindaylight on December 21

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

Precipitation51.3 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: Ozark 2, AR (9 mi away); precipitation: Coal Hill, AR (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Clarksville, AR · 12 mi

Arkansas planting zones →

Questions about 72821

What planting zone is ZIP code 72821?

ZIP code 72821 (Altus, AR) 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 Altus, AR?

The median last spring frost (32 °F) near 72821 is March 30; after April 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Ozark 2 station.

When is the first frost in Altus, AR?

The median first fall frost near 72821 is November 6, giving a median frost-free growing season of 222 days.

When should I plant tomatoes in 72821?

Start tomato seeds indoors around Feb 2 – Feb 16 and set transplants outside around Apr 6 – Apr 20, one to three weeks after the median last frost.

How much rain and snow does 72821 get?

About 51.3 inches of precipitation a year and 1 inches of snowfall (NOAA 1991–2020 normals, Coal Hill station).

How hot do summers get in Altus, AR?

The average high peaks at 92 °F in July, with about 62 days a year at 90 °F or more.

What kind of soil does 72821 have?

The USDA soil survey maps Linker at the center of ZIP 72821: fine sandy loam, well drained, pH about 5.6 (moderately acidic).

Did spring come early in Altus, AR in 2026?

Spring leaf-out near 72821 came on Feb 13 in 2026, 11 days earlier than the 1991–2020 average (Feb 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Altus, AR?

Intermediate onions: the longest day near 72821 is 14 h 33 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 72821 change?

Yes. The 2012 USDA map put 72821 in zone 7b; the 2023 map puts it in zone 8a. The newer map uses 1991–2020 data and more weather stations.