USDA zone 6a in Ohio

−10 to −5 °F avg. annual extreme minimum · 71 locations in this group · NOAA 1991–2020 normals

USDA plant hardiness zone 6a covers 71 locations across Ohio (average annual extreme minimum −10 to −5 °F): Alliance, OH, Arlington, OH, Austinburg, OH, Beavercreek, OH, Bellefontaine, OH, Berlin, OH, and 65 more. Average last spring frost across this group ranges April 8 (Solon) to May 10 (Roaming Shores), and growing seasons run 154–217 days (Roaming Shores to Solon) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Ohio location's own frost dates; the printable planting calendar uses Wellington, this group's median-season location.

USDA zone
6a−10 to −5 °F
Last frost range
Apr 8–May 10avg, 32°F
First frost range
Oct 8–Nov 12avg, 32°F
Growing season range
154–217days

Locations in this group

Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.

Own frost dates per location.
LocationAlso coversNearest stationLast frostFirst frostSeason (days)
AllianceAtwater, Robertsville, LimavilleAkron Canton Rgnl ApApr 24Oct 26184
ArlingtonMount Blanchard, Rawson, Benton Ridge, JeneraFindlay ApApr 19Oct 23185
AustinburgJefferson, Pymatuning NorthAshtabula Co ApMay 2Oct 21171
BeavercreekCedarvilleXenia 6 SseApr 18Oct 24188
BellefontaineEast Liberty, Raymond, West Liberty, De Graff, Russells Point, West Mansfield, +7 moreBellefontaineApr 26Oct 20175
BerlinMillersburg, Walnut Creek, Mount Hope, Winesburg, Killbuck, Holmesville, +2 moreMillersburgMay 2Oct 14164
BlufftonGlandorf, Kalida, Columbus Grove, Pandora, Beaverdam, Belmore, +4 morePandoraApr 23Oct 22180
Broadview HeightsClevelandApr 20Nov 3198
BryanSherwood, Stryker, NeyDefiance Mem ApApr 28Oct 17170
BuchtelAthens OuApr 25Oct 23179
BucyrusIberia, New Washington, Nevada, Tiro, Chatfield, Sulphur Springs, +1 moreBucyrusApr 19Oct 27190
ChesterlandBainbridge, Madison, Chardon, South Russell, Orwell, Burton, +1 moreChardonMay 5Oct 18164
ClaytonTroy, Tipp, Brookville, West Milton, Pleasant Hill, Potsdam, +4 moreDayton Intl ApApr 16Oct 28194
CovingtonRussiaPiqua WwtpApr 18Oct 23186
DaytonNew LebanonDayton McdApr 18Oct 25189
DefianceContinental, Holgate, Hamler, Florida, New BavariaDefianceApr 22Oct 24183
East FultonhamPhilo 3 SwApr 19Oct 25189
EatonCamden, Lewisburg, Gratis, West Alexandria, West Elkton, Verona, +4 moreEatonApr 25Oct 20176
Granville SouthHebron, Buckeye Lake, Kirkersville, Jacksontown, Millersport, Brownsville, +3 moreNewark Heath ApApr 22Oct 18178
Green SpringsOld Fort, Bettsville, Kansas, BurgoonFremontApr 26Oct 23179
GreenvilleVersailles, Arcanum, Bradford, Ansonia, North Star, New Madison, +6 moreGreenville WtpApr 21Oct 20180
HaydenvilleCarbon HillLoganApr 30Oct 14167
HicksvilleHicksvilleApr 28Oct 17170
JeffersonvillePort WilliamWilmington 3 NApr 20Oct 20180
KentAkron Fulton Intl ApApr 24Oct 28186
KentAtwaterRavenna 2 SApr 21Oct 29189
KentonMount Victory, Dola, Dunkirk, PattersonKentonApr 22Oct 24182
LancasterBremen, Sugar Grove, PleasantvilleLancasterApr 22Oct 24183
LimaAda, Waynesfield, New Hampshire, Chippewa Park, St. Johns, McGuffey, +3 moreLima Allen Co ApApr 22Oct 22181
LimaFort Shawnee, Wapakoneta, Gomer, Elida, Spencerville, Fort Jennings, +2 moreLima WwtpApr 24Oct 24182
LondonSouth Vienna, Midway, South SolonLondon Fish HatcheryApr 24Oct 18175
LoudonvilleButler, Gambier, Nellie, Danville, Bladensburg, Glenmont, +3 moreDanville 2 WMay 2Oct 8157
MansfieldAshland, Shelby, Plymouth, Greenwich, Shiloh, Perrysville, +4 moreMansfield Lahm Muni ApApr 26Oct 22177
MansfieldGalion, Lexington, Crestline, Bellville, Hidden LakesMansfield 5 WApr 30Oct 15167
Maria SteinCelina, St. Marys, New Bremen, Coldwater, St. Henry, New Knoxville, +7 moreCelina 3 NeApr 27Oct 19175
MarionMorral, Cardington, Harpster, Prospect, Ashley, Waldo, +5 moreMarion 2 NApr 25Oct 20178
MarysvilleRaymond, Richwood, Milford Center, Magnetic Springs, Unionville CenterMarysvilleApr 19Oct 26188
McCombVan BurenFindlay WpccApr 22Oct 24183
MedinaSullivan, Seville, Lodi, Westfield Center, West Salem, Spencer, +1 moreChippewa LakeApr 29Oct 19172
MontpelierPioneer, Edgerton, West Unity, Edon, Kunkle, Alvordton, +1 moreMontpelierApr 28Oct 18173
Mount VernonFredericktownFredericktown 4 SMay 1Oct 10161
NapoleonWauseon, Archbold, Delta, Liberty Center, Fayette, Pettisville, +3 moreWauseon WtpApr 29Oct 16170
NellieTrinwayCoshocton Wpc PltApr 27Oct 18174
NewarkNashport, Utica, Frazeysburg, Marne, St. Louisville, GratiotNewark Wtr WksApr 29Oct 16167
North BaltimoreDeshler, Hoytville, Milton Center, CustarHoytville 2 NeApr 24Oct 21179
NorwalkCollins, New London, Holiday Lakes, Monroeville, New Haven, North Fairfield, +1 moreNorwalk WwtpApr 25Oct 25183
OxfordFairfieldApr 19Oct 22186
PataskalaNew Albany, EtnaColumbus Port Columbus Intl ApApr 18Oct 27191
PauldingCecil, Antwerp, Melrose, Scott, Oakwood, Payne, +4 morePauldingApr 25Oct 19175
PiquaSidney, Minster, Jackson Center, Rosewood, Botkins, Quincy, +6 moreSidney 1 SApr 27Oct 20175
RittmanOrrville, Creston, Smithville, West Salem, Polk, Sterling, +2 moreWooster Wayne Co ApApr 29Oct 14167
Roaming ShoresOrwell, Andover, Rock CreekDorsetMay 10Oct 10154
SalemColumbiana, Sebring, Guilford Lake, Leetonia, Salineville, Minerva, +7 moreMillport 4 NeMay 2Oct 13165
ShawneeNew Lexington, New Straitsville, Somerset, Junction, East Fultonham, Rendville, +4 moreNew Lexington 2 NwApr 30Oct 17168
SolonTwinsburg, Pepper PikeCleveland Burke ApApr 8Nov 12217
SpringfieldYellow Springs, New Carlisle, South Charleston, Lawrenceville, North Hampton, Donnelsville, +4 moreSpringfield WtpApr 25Oct 19175
StoutsvilleTarlton, HarrisburgCirclevilleApr 17Oct 28192
StreetsboroAurora, Ravenna, Middlefield, Garrettsville, Windham, Orwell, +5 moreHiramMay 1Oct 20170
SugarcreekBaltic, WarsawCoshocton Ag Rsch StnApr 18Oct 28190
SunburyJohnstown, Utica, Centerburg, Hartford (Croton), Chesterville, Marengo, +1 moreCenterburg 2 SeApr 27Oct 17172
SylvaniaBerkey, Swanton, Blissfield, Grand Rapids, Metamora, NeapolisToledo Express ApApr 22Oct 24188
TiffinMcCutchenville, Republic, Attica, Sycamore, Bloomville, New RiegelTiffinApr 23Oct 23184
Upper SanduskyCarey, Wharton, KirbyUpper SanduskyApr 29Oct 17171
UrbanaSt. Paris, North Lewisburg, Mechanicsburg, WoodstockUrbana WwtpApr 24Oct 19179
Van WertDelphos, Ottoville, Convoy, Middle Point, Ohio, Wren, +1 moreVan Wert 1 SApr 21Oct 26187
Wellington *OberlinApr 27Oct 22178
WestonJerry, Rudolph, CygnetBowling Green WwtpApr 22Oct 25186
WoosterDalton, Shreve, Apple Creek, Jeromesville, Fredericksburg, Mount EatonWooster Exp StationApr 30Oct 12163
YoungstownHermitage, Girard, Cortland, Hubbard, Sharon, Clark, +7 moreYoungstown Rgnl ApMay 1Oct 17167
YoungstownLordstown, Warren, Austintown, Niles, Canfield, Howland Center, +8 moreWarren 3 SMay 8Oct 12157
YoungstownNorth Lima, Struthers, East Palestine, Frizzleburg, New Bedford, Bessemer, +15 moreNew Castle 1 NApr 30Oct 23175

* Wellington is this group's median-season location — the calendar below is computed from its data.

Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.

Planting calendar (Wellington, representative)

Computed from Wellington's average frost dates — the median-season location in this Ohiozone 6a group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).

  • Start indoors
  • Plant out
  • Fall sowing
  • First harvest
Planting windows for Wellington (Ohio, zone 6a), this group's representative location.
CropFrost toleranceStart indoorsPlant outFirst harvestFall plantingSeason fit
TomatoTenderMar 2 – Mar 16May 4 – May 11Jul 3 – Jul 23matures comfortably
PepperVery tenderFeb 16 – Mar 2May 11 – May 18Jul 10 – Aug 9matures comfortably
CucumberTenderMar 30 – Apr 6May 4 – May 11Jun 23 – Jul 13matures comfortably
Summer squash / zucchiniTenderMay 4 – May 11Jun 18 – Jul 3matures comfortably
Bush beanTenderMay 4 – May 11Jun 23 – Jul 3Aug 23 – Sep 2matures comfortably
Sweet cornTenderApr 27 – May 11Jun 26 – Jul 26matures comfortably
BasilVery tenderMar 16 – Mar 30May 4 – May 11Jun 3 – Jun 18matures comfortably
LettuceHalf-hardyMar 16 – Mar 30Mar 30 – Apr 13May 14 – May 29Aug 9 – Aug 24matures comfortably
PeaHardyMar 16 – Mar 30May 10 – May 25Jul 30 – Aug 14matures comfortably
SpinachHardyMar 16 – Mar 30Apr 25 – May 5Aug 19 – Aug 29matures comfortably
CarrotHalf-hardyApr 6 – Apr 13Jun 5 – Jun 25Jul 20 – Aug 9matures comfortably
BroccoliHalf-hardyMar 2 – Mar 16Mar 30 – Apr 13May 24 – Jun 13Jul 25 – Aug 14matures comfortably

Which crops fit this growing season

Using Wellington's own 178-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.

Frost & freeze dates (Wellington)

From NOAA's 1991–2020 Climate Normals at station USC00336196. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020), Wellington.
ThresholdLast spring — avgLast spring — 90%-safeFirst fall — avgFirst fall — 90%-safeSeason (days)
36°FMay 7May 23Oct 10Oct 24155
32°F (freeze)Apr 27May 14Oct 22Nov 4178
28°FApr 15May 1Nov 3Nov 17203
24°FApr 2Apr 16Nov 14Nov 30226

Growing degree days

Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 71 locations is 3,156; Wellington's own reading is shown below.

Annual growing degree days for Wellington (°F·days, NOAA 1991–2020).
Model°F·daysUsed for
Base 50°F (warm-season)2,959standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season)5,137cool-season crops (brassicas, greens)

Hardiness zone 6a in Ohio

Zone 6a means an average annual extreme minimum winter temperature of about −10 to −5 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Ohio spans 4 hardiness zones in this dataset — see all Ohio locations for the full range, including zones5b, 6b, 7a.

Explore zone 6a in other states at zone 6a, or see all USDA hardiness zones.

Frequently asked questions

What does USDA hardiness zone 6a mean in Ohio?
Zone 6a means an average annual extreme minimum winter temperature of −10 to −5 °F — the standard USDA measure of which perennials survive winter. 71 locations in Ohio fall in this zone. It does not set planting dates; see the frost calendar below for that.
Where in Ohio's zone 6a is the growing season longest?
Solon runs the longest season on this page at about 217 days; Roaming Shores is shortest at about 154 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
When should I plant tomatoes in Ohio's zone 6a?
Using Wellington's frost dates (this page's median-season location): start seeds indoors about Mar 2 – Mar 16, then transplant outside about May 4 – May 11. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
Does every location in Ohio's zone 6a have the same frost dates?
No — they do not all share a weather station, so frost dates vary by a week or more across the 71 locations listed (see the table above for each location's own dates).

Sources & method

Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.