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

Planting zone for 45331 — Greenville, OH

ZIP code 45331 (Greenville, Darke County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 21 and the first fall frost October 20.

Where ZIP 45331 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostApr 21
First frostOct 20
2012 zone5b

Was 5b 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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Greenville, OH…

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 Greenville, OH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 21median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 6
Growing season180 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 9 and returns around October 31.

From the NOAA station Greenville Wtp, OH — within 1 mile, elevation 1,030 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 45331

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 10 – Mar 24
SpinachSow outdoors · Mar 10 – Mar 31
Broccoli, cabbageStart indoors · Feb 10 – Feb 24
Broccoli, cabbageTransplant · Mar 31 – Apr 14
Onion setsPlant outdoors · Mar 24 – Apr 7
PotatoesPlant outdoors · Mar 31 – Apr 14
LettuceSow outdoors · Mar 24 – Apr 7
Carrots, beetsSow outdoors · Mar 31 – Apr 14
TomatoesStart indoors · Feb 24 – Mar 10
TomatoesTransplant · Apr 28 – May 12
Peppers, eggplantStart indoors · Feb 10 – Feb 24
Peppers, eggplantTransplant · May 5 – May 19
BeansSow outdoors · Apr 28 – May 12
Sweet cornSow outdoors · Apr 28 – May 12
Cucumbers, squashSow outdoors · Apr 28 – May 12
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 21) and first fall frost (Oct 20) 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 45331 came on Mar 10 — 21 days earlier than the 1991–2020 average (Mar 31).

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).

Soil in Greenville, OH

The soil mapped at the center of ZIP 45331 is Eldean — loam, well drained.

TextureLoama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2%moderate
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Eldean 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 45331; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Greenville, OH

Summer high85 °Faverage high, July
Winter low19 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights126nights a year at 32 °F or less
Growing degree days3,360base 50 °F — the season’s usable heat
Longest day15 h 02 mindaylight on June 21
Shortest day9 h 19 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation40.3 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 35 °F, low 19 °F 35°19° JanFebruary: average high 39 °F, low 21 °F 39°21° FebMarch: average high 50 °F, low 30 °F 50°30° MarApril: average high 63 °F, low 40 °F 63°40° AprMay: average high 73 °F, low 52 °F 73°52° MayJune: average high 82 °F, low 61 °F 82°61° JunJuly: average high 85 °F, low 64 °F 85°64° JulAugust: average high 83 °F, low 61 °F 83°61° AugSeptember: average high 78 °F, low 53 °F 78°53° SepOctober: average high 66 °F, low 42 °F 66°42° OctNovember: average high 52 °F, low 33 °F 52°33° NovDecember: average high 40 °F, low 25 °F 40°25° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.84 in precipitation 2.8 JanFebruary: 2.23 in precipitation 2.2 FebMarch: 3.23 in precipitation 3.2 MarApril: 4.18 in precipitation 4.2 AprMay: 4.31 in precipitation 4.3 MayJune: 4.42 in precipitation 4.4 JunJuly: 3.95 in precipitation 4.0 JulAugust: 3.40 in precipitation 3.4 AugSeptember: 2.75 in precipitation 2.8 SepOctober: 2.90 in precipitation 2.9 OctNovember: 3.17 in precipitation 3.2 NovDecember: 2.88 in precipitation 2.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Greenville Wtp, OH (within 1 mile); precipitation: Greenville Wtp, OH (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

453526a
Palestine, OH · 6 mi
453036a
Ansonia, OH · 8 mi
453286a
Gettysburg, OH · 8 mi
453466a
New Madison, OH · 9 mi
453326a
Hollansburg, OH · 9 mi
453906a
Union City, OH · 10 mi
453086a
Bradford, OH · 10 mi
453046a
Arcanum, OH · 10 mi

Ohio planting zones →

Questions about 45331

What planting zone is ZIP code 45331?

ZIP code 45331 (Greenville, OH) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Greenville, OH?

The median last spring frost (32 °F) near 45331 is April 21; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Greenville Wtp station.

When is the first frost in Greenville, OH?

The median first fall frost near 45331 is October 20, giving a median frost-free growing season of 180 days.

When should I plant tomatoes in 45331?

Start tomato seeds indoors around Feb 24 – Mar 10 and set transplants outside around Apr 28 – May 12, one to three weeks after the median last frost.

How much rain and snow does 45331 get?

About 40.3 inches of precipitation a year (NOAA 1991–2020 normals, Greenville Wtp station).

How hot do summers get in Greenville, OH?

The average high peaks at 85 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 45331 have?

The USDA soil survey maps Eldean at the center of ZIP 45331: loam, well drained, pH about 6.5 (neutral).

Did spring come early in Greenville, OH in 2026?

Spring leaf-out near 45331 came on Mar 10 in 2026, 21 days earlier than the 1991–2020 average (Mar 31), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Greenville, OH?

Long-day onions: the longest day near 45331 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 45331 change?

Yes. The 2012 USDA map put 45331 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.