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

Planting zone for 30742 — Fort Oglethorpe, GA

ZIP code 30742 (Fort Oglethorpe, Catoosa County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is April 6 and the first fall frost October 30.

Where ZIP 30742 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 frostApr 6

First frostOct 30

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 Fort Oglethorpe, 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 Fort Oglethorpe, GA

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 6median — 50% chance of a later frost

Safe for tender plantsApril 23only 10% chance of frost after

First fall frostOctober 30median — 10% chance by Oct 17

Growing season205 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 27 and returns around November 6.

From the NOAA station Chickamauga Pk Larc, GA — 2 miles away, elevation 781 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 30742

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 23 – Mar 9

SpinachSow outdoors · Feb 23 – Mar 16

Broccoli, cabbageStart indoors · Jan 26 – Feb 9

Broccoli, cabbageTransplant · Mar 16 – Mar 30

Onion setsPlant outdoors · Mar 9 – Mar 23

PotatoesPlant outdoors · Mar 16 – Mar 30

LettuceSow outdoors · Mar 9 – Mar 23

Carrots, beetsSow outdoors · Mar 16 – Mar 30

TomatoesStart indoors · Feb 9 – Feb 23

TomatoesTransplant · Apr 13 – Apr 27

Peppers, eggplantStart indoors · Jan 26 – Feb 9

Peppers, eggplantTransplant · Apr 20 – May 4

BeansSow outdoors · Apr 13 – Apr 27

Sweet cornSow outdoors · Apr 13 – Apr 27

Cucumbers, squashSow outdoors · Apr 13 – Apr 27

Fall lettuce, spinachSow outdoors · Sep 4 – Sep 18

GarlicPlant cloves · Oct 16 – Nov 20

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 6) and first fall frost (Oct 30) 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 30742 came on Feb 20 — about the same time as the 1991–2020 average (Feb 18).

average
Feb 182026
Feb 20

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 Georgia

572 plants native to the lower 48 states, recorded in Georgia, 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 Fort Oglethorpe, GA.

Soil in Fort Oglethorpe, GA

The soil mapped at the center of ZIP 30742 is Lyerly — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up

pH5.5moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Lyerly silty clay loam, 2 to 6 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 30742; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Fort Oglethorpe, GA

Summer high89 °Faverage high, July

Winter low29 °Faverage low, January

Hot days51days a year at 90 °F or more

Freezing nights84nights a year at 32 °F or less

Growing degree days4,558base 50 °F — the season’s usable heat

Longest day14 h 30 mindaylight on June 21

Shortest day9 h 48 mindaylight on December 21

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

Precipitation56.5 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: Chickamauga Pk Larc, GA (2 mi away); precipitation: Chickamauga Pk Larc, GA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8a.

307418a

Rossville, GA · 2 mi

374128a

Chattanooga, TN · 4 mi

374078a

Chattanooga, TN · 5 mi

374108a

Chattanooga, TN · 6 mi

307258a

Flintstone, GA · 6 mi

374118a

Chattanooga, TN · 6 mi

307268a

Graysville, GA · 6 mi

374048a

Chattanooga, TN · 7 mi

Georgia planting zones →

Questions about 30742

What planting zone is ZIP code 30742?

ZIP code 30742 (Fort Oglethorpe, GA) 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 Fort Oglethorpe, GA?

The median last spring frost (32 °F) near 30742 is April 6; after April 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Chickamauga Pk Larc station.

When is the first frost in Fort Oglethorpe, GA?

The median first fall frost near 30742 is October 30, giving a median frost-free growing season of 205 days.

When should I plant tomatoes in 30742?

Start tomato seeds indoors around Feb 9 – Feb 23 and set transplants outside around Apr 13 – Apr 27, one to three weeks after the median last frost.

How much rain and snow does 30742 get?

About 56.5 inches of precipitation a year and 1 inches of snowfall (NOAA 1991–2020 normals, Chickamauga Pk Larc station).

How hot do summers get in Fort Oglethorpe, GA?

The average high peaks at 89 °F in July, with about 51 days a year at 90 °F or more.

What kind of soil does 30742 have?

The USDA soil survey maps Lyerly at the center of ZIP 30742: silty clay loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Fort Oglethorpe, GA in 2026?

Spring leaf-out near 30742 came on Feb 20 in 2026, about the same as the 1991–2020 average (Feb 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Fort Oglethorpe, GA?

Intermediate onions: the longest day near 30742 is 14 h 30 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 30742 change?

Yes. The 2012 USDA map put 30742 in zone 7b; the 2023 map puts it in zone 8a. The newer map uses 1991–2020 data and more weather stations.