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

Planting zone for 30274 — Riverdale, GA

ZIP code 30274 (Riverdale, Clayton County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 25 and the first fall frost November 12.

Where ZIP 30274 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 25

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 Riverdale, 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 Riverdale, GA

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 25median — 50% chance of a later frost

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

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

Growing season235 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 8 and returns around November 28.

From the NOAA station Jonesboro, GA — 3 miles away, elevation 932 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 30274

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 11 – Feb 25

SpinachSow outdoors · Feb 11 – Mar 4

Broccoli, cabbageStart indoors · Jan 14 – Jan 28

Broccoli, cabbageTransplant · Mar 4 – Mar 18

Onion setsPlant outdoors · Feb 25 – Mar 11

PotatoesPlant outdoors · Mar 4 – Mar 18

LettuceSow outdoors · Feb 25 – Mar 11

Carrots, beetsSow outdoors · Mar 4 – Mar 18

TomatoesStart indoors · Jan 28 – Feb 11

TomatoesTransplant · Apr 1 – Apr 15

Peppers, eggplantStart indoors · Jan 14 – Jan 28

Peppers, eggplantTransplant · Apr 8 – Apr 22

BeansSow outdoors · Apr 1 – Apr 15

Sweet cornSow outdoors · Apr 1 – Apr 15

Cucumbers, squashSow outdoors · Apr 1 – Apr 15

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 25) 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 30274 came on Feb 14 — 3 days later than the 1991–2020 average (Feb 11).

average
Feb 112026
Feb 14

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 Riverdale, GA.

Soil in Riverdale, GA

The soil mapped at the center of ZIP 30274 is Pacolet — sandy loam, well drained.

TextureSandy loamdrains and warms fast; dries out and needs more feeding

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

DrainageWell drainednatural drainage class

Organic matter1.25%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Pacolet sandy loam, 6 to 10 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 30274; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Riverdale, GA

Summer high90 °Faverage high, July

Winter low32 °Faverage low, January

Hot days59days a year at 90 °F or more

Freezing nights49nights a year at 32 °F or less

Growing degree days5,105base 50 °F — the season’s usable heat

Longest day14 h 23 mindaylight on June 21

Shortest day9 h 55 mindaylight on December 21

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

Precipitation52.9 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: Jonesboro, GA (3 mi away); precipitation: Jonesboro, GA (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.

Forest Park, GA · 4 mi

Forest Park, GA · 5 mi

302368b

Jonesboro, GA · 5 mi

All 2 ZIP codes in Riverdale → · Georgia planting zones →

Questions about 30274

What planting zone is ZIP code 30274?

ZIP code 30274 (Riverdale, 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 Riverdale, GA?

The median last spring frost (32 °F) near 30274 is March 25; after April 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Jonesboro station.

When is the first frost in Riverdale, GA?

The median first fall frost near 30274 is November 12, giving a median frost-free growing season of 235 days.

When should I plant tomatoes in 30274?

Start tomato seeds indoors around Jan 28 – Feb 11 and set transplants outside around Apr 1 – Apr 15, one to three weeks after the median last frost.

How much rain and snow does 30274 get?

About 52.9 inches of precipitation a year and 1 inches of snowfall (NOAA 1991–2020 normals, Jonesboro station).

How hot do summers get in Riverdale, GA?

The average high peaks at 90 °F in July, with about 59 days a year at 90 °F or more.

What kind of soil does 30274 have?

The USDA soil survey maps Pacolet at the center of ZIP 30274: sandy loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Riverdale, GA in 2026?

Spring leaf-out near 30274 came on Feb 14 in 2026, 3 days later than the 1991–2020 average (Feb 11), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Riverdale, GA?

Intermediate onions: the longest day near 30274 is 14 h 23 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 30274 change?

Yes. The 2012 USDA map put 30274 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.