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

Planting zone for 44828 — Flat Rock, OH

ZIP code 44828 (Flat Rock, Seneca County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 25 and the first fall frost October 25.

Where ZIP 44828 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 25
First frostOct 25
2012 zone6a

Same zone as on the 2012 map. 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 Flat Rock, 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 Flat Rock, OH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 25median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 25median — 10% chance by Oct 11
Growing season183 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 12 and returns around November 5.

From the NOAA station Norwalk Wwtp, OH — 13 miles away, elevation 669 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 44828

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 14 – Mar 28
SpinachSow outdoors · Mar 14 – Apr 4
Broccoli, cabbageStart indoors · Feb 14 – Feb 28
Broccoli, cabbageTransplant · Apr 4 – Apr 18
Onion setsPlant outdoors · Mar 28 – Apr 11
PotatoesPlant outdoors · Apr 4 – Apr 18
LettuceSow outdoors · Mar 28 – Apr 11
Carrots, beetsSow outdoors · Apr 4 – Apr 18
TomatoesStart indoors · Feb 28 – Mar 14
TomatoesTransplant · May 2 – May 16
Peppers, eggplantStart indoors · Feb 14 – Feb 28
Peppers, eggplantTransplant · May 9 – May 23
BeansSow outdoors · May 2 – May 16
Sweet cornSow outdoors · May 2 – May 16
Cucumbers, squashSow outdoors · May 2 – May 16
Fall lettuce, spinachSow outdoors · Aug 30 – Sep 13
GarlicPlant cloves · Oct 11 – Nov 15
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 25) and first fall frost (Oct 25) 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 44828 came on Mar 21 — 13 days earlier than the 1991–2020 average (Apr 3).

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 6a in Ohio

565 plants native to the lower 48 states, recorded in Ohio, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 70

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 109

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 202

American bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °FAmerican speedwell0.8 ft · blooms mid summer · low shade tolerance · to −38 °FAmerican vetch1.3 ft · blooms late spring · high shade tolerance · to −38 °F

Grasses 164

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °F

Vines 8

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °F

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 Flat Rock, OH.

Soil in Flat Rock, OH

The soil mapped at the center of ZIP 44828 is Milton — silt loam, well drained.

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

Map unit: Milton silt loam, 0 to 2 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 44828; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Flat Rock, OH

Summer high83 °Faverage high, July
Winter low19 °Faverage low, January
Hot days15days a year at 90 °F or more
Freezing nights124nights a year at 32 °F or less
Growing degree days3,097base 50 °F — the season’s usable heat
Longest day15 h 09 mindaylight on June 21
Shortest day9 h 12 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation40.7 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 33 °F, low 19 °F 33°19° JanFebruary: average high 36 °F, low 20 °F 36°20° FebMarch: average high 46 °F, low 28 °F 46°28° MarApril: average high 59 °F, low 38 °F 59°38° AprMay: average high 70 °F, low 50 °F 70°50° MayJune: average high 79 °F, low 60 °F 79°60° JunJuly: average high 83 °F, low 64 °F 83°64° JulAugust: average high 81 °F, low 62 °F 81°62° AugSeptember: average high 76 °F, low 55 °F 76°55° SepOctober: average high 63 °F, low 43 °F 63°43° OctNovember: average high 50 °F, low 34 °F 50°34° NovDecember: average high 39 °F, low 25 °F 39°25° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.90 in precipitation 2.9 JanFebruary: 2.56 in precipitation 2.6 FebMarch: 2.77 in precipitation 2.8 MarApril: 3.84 in precipitation 3.8 AprMay: 4.02 in precipitation 4.0 MayJune: 4.36 in precipitation 4.4 JunJuly: 4.35 in precipitation 4.3 JulAugust: 3.50 in precipitation 3.5 AugSeptember: 3.54 in precipitation 3.5 SepOctober: 3.08 in precipitation 3.1 OctNovember: 2.91 in precipitation 2.9 NovDecember: 2.86 in precipitation 2.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Norwalk Wwtp, OH (13 mi away); precipitation: Bellevue 0.6 N, OH (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

2 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

448116a
Bellevue, OH · 1 mi
434106b
Clyde, OH · 7 mi
448476a
Monroeville, OH · 8 mi
448676a
Republic, OH · 9 mi
448366a
Green Springs, OH · 11 mi
448246b
Castalia, OH · 11 mi
448076a
Attica, OH · 12 mi
448906a
Willard, OH · 13 mi

Ohio planting zones →

Questions about 44828

What planting zone is ZIP code 44828?

ZIP code 44828 (Flat Rock, 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 Flat Rock, OH?

The median last spring frost (32 °F) near 44828 is April 25; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Norwalk Wwtp station.

When is the first frost in Flat Rock, OH?

The median first fall frost near 44828 is October 25, giving a median frost-free growing season of 183 days.

When should I plant tomatoes in 44828?

Start tomato seeds indoors around Feb 28 – Mar 14 and set transplants outside around May 2 – May 16, one to three weeks after the median last frost.

How much rain and snow does 44828 get?

About 40.7 inches of precipitation a year (NOAA 1991–2020 normals, Bellevue 0.6 N station).

How hot do summers get in Flat Rock, OH?

The average high peaks at 83 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 44828 have?

The USDA soil survey maps Milton at the center of ZIP 44828: silt loam, well drained, pH about 6.5 (neutral).

Did spring come early in Flat Rock, OH in 2026?

Spring leaf-out near 44828 came on Mar 21 in 2026, 13 days earlier than the 1991–2020 average (Apr 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Flat Rock, OH?

Long-day onions: the longest day near 44828 is 15 h 09 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).