USGrowersGuide
ES

State guide

Planting zones in Ohio

Ohio spans USDA zones 6a to 7a across its 1,212 ZIP codes, so there is no single zone for the state and anyone who gives you one is rounding. 54% of its ZIP codes are zone 6b; the rest are not.

USDA zones 6a–7a 3 zones across the state
ZIP codes 1,212 1,212 have a NOAA station within range
Weather stations 130 In Ohio, NOAA 1991–2020 normals

Your ZIP code

Get the exact answer for your address

Everything above describes Ohio as a whole. Hardiness zones and freeze dates are published per ZIP code, so yours is exact — enter it and this page will tell you your zone, which NOAA station it comes from and how far away that station is.

Works for all 40,502 US ZIP codes. Freeze dates need a NOAA station within 100 km; where there is none, the page says so rather than estimating one.

Which zone you are in depends where you are

Ohio covers 3 hardiness zones. A guide that gives the state one zone has picked whichever is largest and rounded everyone else into it — which is fine for the 54% in zone 6b and wrong for the other 46%. Here is the actual split, by ZIP code.

Zone ZIP codes Share  
6b 651 54%
6a 512 42%
7a 49 4%

Zones are published per ZIP code, so yours is exact even though the state's is not. The hardiness tool will tell you which one you are in.

Your freeze dates

Last spring freeze April 8 – May 10
First fall freeze October 8 – November 12

Those are the earliest and latest medians among the 130 stations in Ohio with an ordinary freeze window — not an average, and not one station standing in for the rest. Half of years freeze later than a station's own median.

Your growing season

NOAA publishes a growing-season length for each station, and across the 130 stations in Ohio it runs 154–217 days . That figure is published, not computed from the two freeze dates — subtracting one from the other gives the wrong answer wherever a season crosses New Year. Mean summer high (June–August) runs 79–86 °F , below the 90 °F point where cool-season crops reliably bolt.

The ends of each range, named

A range with no station behind it cannot be checked, and Ohio has too many stations to table them all. So every figure above is reported here with the station standing at each end of it, by name and NOAA ID. No station on this page represents Ohio — these are its edges, which is a different claim.

Measure Earliest / lowest Station Latest / highest Station
Last spring freeze April 8 Cleveland Burke AP, OH USW00004853 May 10 Dorset, OH USC00332251
First fall freeze October 8 Danville 2 W, OH USC00332044 November 12 Cleveland Burke AP, OH USW00004853
Growing season 154 days Dorset, OH USC00332251 217 days Cleveland Burke AP, OH USW00004853
Mean summer high 79 °F Dorset, OH USC00332251 86 °F Lucasville, OH USC00334770

These are medians, not averages — NOAA publishes freeze dates as a probability distribution, and half of years freeze later than the date shown.

When to start seeds in Ohio

Every spring job for 63 crop dates, counted from this state's own last spring freeze. Each is a range across all 130 stations — the earliest and latest that job falls anywhere in Ohio — because no one station speaks for a whole state. The ranges are wide on purpose: that width is the state.

Crop Job When Offset
Green Onions Start indoors February 11 – March 15 8 weeks before
Peppers Start indoors February 11 – March 15 8 weeks before
Broccoli Start indoors February 25 – March 29 6 weeks before
Cabbage Start indoors February 25 – March 29 6 weeks before
Collards Start indoors February 25 – March 29 6 weeks before
Kale Start indoors February 25 – March 29 6 weeks before
Leaf Lettuce Start indoors February 25 – March 29 6 weeks before
Peas Direct sow February 25 – March 29 6 weeks before
Spinach Direct sow February 25 – March 29 6 weeks before
Sweet Potato Start indoors February 25 – March 29 6 weeks before
Tomatoes Start indoors February 25 – March 29 6 weeks before
Bok Choy Start indoors March 4 – April 5 5 weeks before
Kohlrabi Start indoors March 4 – April 5 5 weeks before
Swiss Chard Start indoors March 4 – April 5 5 weeks before
Arugula Direct sow March 11 – April 12 4 weeks before
Baby Salad Greens Direct sow March 11 – April 12 4 weeks before
Beets Direct sow March 11 – April 12 4 weeks before
Green Onions Direct sow March 11 – April 12 4 weeks before
Mustard Greens Direct sow March 11 – April 12 4 weeks before
Okra Start indoors March 11 – April 12 4 weeks before
Radishes Direct sow March 11 – April 12 4 weeks before
Turnips Direct sow March 11 – April 12 4 weeks before
Cabbage Set out March 18 – April 19 3 weeks before
Carrots Direct sow March 18 – April 19 3 weeks before
Collards Direct sow March 18 – April 19 3 weeks before
Collards Set out March 18 – April 19 3 weeks before
Cucumbers Start indoors March 18 – April 19 3 weeks before
Green Onions Set out March 18 – April 19 3 weeks before
Kale Direct sow March 18 – April 19 3 weeks before
Kale Set out March 18 – April 19 3 weeks before
Kohlrabi Direct sow March 18 – April 19 3 weeks before
Kohlrabi Set out March 18 – April 19 3 weeks before
Leaf Lettuce Direct sow March 18 – April 19 3 weeks before
Pumpkins Start indoors March 18 – April 19 3 weeks before
Summer Squash Start indoors March 18 – April 19 3 weeks before
Winter Squash Start indoors March 18 – April 19 3 weeks before
Zucchini Start indoors March 18 – April 19 3 weeks before
Bok Choy Direct sow March 25 – April 26 2 weeks before
Bok Choy Set out March 25 – April 26 2 weeks before
Broccoli Set out March 25 – April 26 2 weeks before
Cilantro Direct sow March 25 – April 26 2 weeks before
Leaf Lettuce Set out March 25 – April 26 2 weeks before
Swiss Chard Direct sow March 25 – April 26 2 weeks before
Swiss Chard Set out March 25 – April 26 2 weeks before
Dill Direct sow April 1 – May 3 1 week before
Bush Beans Direct sow April 15 – May 17 1 week after
Cucumbers Set out April 15 – May 17 1 week after
Pumpkins Direct sow April 15 – May 17 1 week after
Pumpkins Set out April 15 – May 17 1 week after
Summer Squash Direct sow April 15 – May 17 1 week after
Summer Squash Set out April 15 – May 17 1 week after
Sweet Corn Direct sow April 15 – May 17 1 week after
Tomatoes Set out April 15 – May 17 1 week after
Winter Squash Direct sow April 15 – May 17 1 week after
Winter Squash Set out April 15 – May 17 1 week after
Zucchini Direct sow April 15 – May 17 1 week after
Zucchini Set out April 15 – May 17 1 week after
Cucumbers Direct sow April 22 – May 24 2 weeks after
Okra Direct sow April 22 – May 24 2 weeks after
Okra Set out April 22 – May 24 2 weeks after
Peppers Set out April 22 – May 24 2 weeks after
Southern Peas Direct sow April 22 – May 24 2 weeks after
Sweet Potato Set out April 22 – May 24 2 weeks after

The week offsets are conventional extension guidance and vary by variety; the freeze dates they are counted from are measured. For a single date rather than a range, run when do I start my seeds? with your own ZIP code.

What survives the winter changes across Ohio

Of 74 perennial fruits, nuts, berries, vegetables and herbs, 58 come through the winter in zone 7a and only 51 in zone 6a. Winter hardiness runs on the zone alone, so each row below is exact for the ZIP codes in it.

Zone ZIPs Survive Fail for being too warm
6a 512 51 of 74 0
6b 651 51 of 74 0
7a 49 58 of 74 1

The last column is the counterintuitive one. Most temperate fruit needs a documented number of hours below about 45 °F to break dormancy and set a crop, so an apple fails in a winter that is too warm; currants and rhubarb cook in the summer heat that comes with it. See the full list with reasons.

Your own ZIP

Work out your own dates

Each of these takes a ZIP code and answers for that ZIP alone, citing the station it used and how far away it is. There is a ZIP box in the header of every page.

Metro areas in Ohio

15 metro areas here have its own page, with the freeze dates from every station serving it, a spring calendar built from those stations, and every ZIP code in it listed with that ZIP code's exact zone and nearest station.

Counties in Ohio

21 countys here have its own page, listing every ZIP code in it with that ZIP code's exact zone and nearest station. These are the smaller places outside the metro areas above — where most of Ohio's ZIP codes actually are.

Other states to compare

All 52 states · All 388 metro areas · All county pages

Gear

If you want to act on this

Each link opens an Amazon search rather than a product we picked. We have not tested these and do not rank them — the search is the honest version, and you choose.

As an Amazon Associate we earn from qualifying purchases. That costs you nothing extra, and it buys no influence over anything on this site: the dates come from NOAA normals and the zones from the USDA, and no product affects either.

Sources

Where these numbers come from

The hardiness zone is the USDA 2023 Plant Hardiness Zone Map, published per ZIP code by PRISM at Oregon State. The freeze dates, growing seasons and summer highs are NOAA's 1991–2020 Climate Normals, read from every station in Ohio. Which ZIP codes are in Ohio comes from the Census ZIP-to-county relation, since a county's federal code begins with its state's. Nothing here is estimated.

This page names no single station for Ohio on purpose. Picking one to represent a state sounds reasonable and is not — the same reason the metro pages refuse it, only more so at this size. Instead every range names the station at each end, so you can check both without either one being made to speak for the state.

All states · All metro areas