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

Planting zone for 31091 — Unadilla, GA

ZIP code 31091 (Unadilla, Dooly County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 20 and the first fall frost November 12.

Where ZIP 31091 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 20

First frostNov 12

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 Unadilla, GA…

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 Unadilla, GA

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 6only 10% chance of frost after

First fall frostNovember 12median — 10% chance by Oct 31

Growing season239 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 4 and returns around November 27.

From the NOAA station Hawkinsville, GA — 14 miles away, elevation 246 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 31091

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 17 – Oct 1

GarlicPlant cloves · Oct 29 – Dec 3

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 20) and first fall frost (Nov 12) 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 31091 came on Feb 10 — 8 days later than the 1991–2020 average (Feb 2).

average
Feb 22026
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 8b in Georgia

590 plants native to the lower 48 states, recorded in Georgia, 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 Unadilla, GA.

Soil in Unadilla, GA

The soil mapped at the center of ZIP 31091 is Dothan — loamy sand, well drained.

TextureLoamy sanddrains and warms fast; dries out and needs more feeding

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

DrainageWell drainednatural drainage class

Organic matter0.25%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Dothan loamy sand, 0 to 2 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 31091; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Unadilla, GA

Summer high92 °Faverage high, July

Winter low35 °Faverage low, January

Hot days83days a year at 90 °F or more

Freezing nights40nights a year at 32 °F or less

Growing degree days5,821base 50 °F — the season’s usable heat

Longest day14 h 16 mindaylight on June 21

Shortest day10 h 02 mindaylight on December 21

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

Precipitation49.7 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: Hawkinsville, GA (14 mi away); precipitation: Hawkinsville 9.1 Nw, GA (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

310708b

Pinehurst, GA · 6 mi

310138b

Clinchfield, GA · 7 mi

Hawkinsville, GA · 13 mi

310078b

Byromville, GA · 13 mi

Georgia planting zones →

Questions about 31091

What planting zone is ZIP code 31091?

ZIP code 31091 (Unadilla, GA) 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 Unadilla, GA?

The median last spring frost (32 °F) near 31091 is March 20; after April 6 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hawkinsville station.

When is the first frost in Unadilla, GA?

The median first fall frost near 31091 is November 12, giving a median frost-free growing season of 239 days.

When should I plant tomatoes in 31091?

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 31091 get?

About 49.7 inches of precipitation a year (NOAA 1991–2020 normals, Hawkinsville 9.1 Nw station).

How hot do summers get in Unadilla, GA?

The average high peaks at 92 °F in July, with about 83 days a year at 90 °F or more.

What kind of soil does 31091 have?

The USDA soil survey maps Dothan at the center of ZIP 31091: loamy sand, well drained, pH about 5.3 (strongly acidic).

Did spring come early in Unadilla, GA in 2026?

Spring leaf-out near 31091 came on Feb 10 in 2026, 8 days later than the 1991–2020 average (Feb 2), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Unadilla, GA?

Short-day onions: the longest day near 31091 is 14 h 16 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.

Did the zone for 31091 change?

Yes. The 2012 USDA map put 31091 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.