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

Planting zone for 45299 — Cincinnati, OH

ZIP code 45299 (Cincinnati, Hamilton County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 22 and the first fall frost October 18.

Where ZIP 45299 is

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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 22
First frostOct 18
2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Cincinnati, 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 Cincinnati, OH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 22median — 50% chance of a later frost
Safe for tender plantsMay 10only 10% chance of frost after
First fall frostOctober 18median — 10% chance by Oct 5
Growing season178 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 8 and returns around October 27.

From the NOAA station Hamilton Butler Co. Regional Airport, OH — 7 miles away, elevation 633 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 45299

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 11 – Mar 25
SpinachSow outdoors · Mar 11 – Apr 1
Broccoli, cabbageStart indoors · Feb 11 – Feb 25
Broccoli, cabbageTransplant · Apr 1 – Apr 15
Onion setsPlant outdoors · Mar 25 – Apr 8
PotatoesPlant outdoors · Apr 1 – Apr 15
LettuceSow outdoors · Mar 25 – Apr 8
Carrots, beetsSow outdoors · Apr 1 – Apr 15
TomatoesStart indoors · Feb 25 – Mar 11
TomatoesTransplant · Apr 29 – May 13
Peppers, eggplantStart indoors · Feb 11 – Feb 25
Peppers, eggplantTransplant · May 6 – May 20
BeansSow outdoors · Apr 29 – May 13
Sweet cornSow outdoors · Apr 29 – May 13
Cucumbers, squashSow outdoors · Apr 29 – May 13
Fall lettuce, spinachSow outdoors · Aug 23 – Sep 6
GarlicPlant cloves · Oct 4 – Nov 8
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 22) and first fall frost (Oct 18) 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 45299 came on Mar 8 — 9 days earlier than the 1991–2020 average (Mar 17).

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 6b in Ohio

570 plants native to the lower 48 states, recorded in Ohio, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 71

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 203

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 165

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 10

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 °Fgraybark grape50 ft · blooms late spring · medium shade tolerance · to −8 °Fheartleaf peppervine2 ft · blooms late spring · low shade tolerance · to −8 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °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 Cincinnati, OH.

Soil in Cincinnati, OH

The soil mapped at the center of ZIP 45299 is Alfic Udarents — silty clay loam, moderately well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter0.5%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land-Alfic Udarents complex, fragipan substratum over till, 0 to 12 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 45299; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Cincinnati, OH

Summer high87 °Faverage high, July
Winter low22 °Faverage low, January
Hot days28days a year at 90 °F or more
Freezing nights115nights a year at 32 °F or less
Growing degree days3,637base 50 °F — the season’s usable heat
Longest day14 h 56 mindaylight on June 21
Shortest day9 h 24 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation44.3 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 40 °F, low 22 °F 40°22° JanFebruary: average high 44 °F, low 23 °F 44°23° FebMarch: average high 54 °F, low 32 °F 54°32° MarApril: average high 67 °F, low 42 °F 67°42° AprMay: average high 75 °F, low 52 °F 75°52° MayJune: average high 83 °F, low 61 °F 83°61° JunJuly: average high 87 °F, low 64 °F 87°64° JulAugust: average high 86 °F, low 62 °F 86°62° AugSeptember: average high 80 °F, low 54 °F 80°54° SepOctober: average high 68 °F, low 42 °F 68°42° OctNovember: average high 55 °F, low 32 °F 55°32° NovDecember: average high 44 °F, low 26 °F 44°26° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.27 in precipitation 3.3 JanFebruary: 3.02 in precipitation 3.0 FebMarch: 3.91 in precipitation 3.9 MarApril: 4.65 in precipitation 4.7 AprMay: 4.88 in precipitation 4.9 MayJune: 4.63 in precipitation 4.6 JunJuly: 3.90 in precipitation 3.9 JulAugust: 3.05 in precipitation 3.0 AugSeptember: 3.18 in precipitation 3.2 SepOctober: 3.19 in precipitation 3.2 OctNovember: 3.17 in precipitation 3.2 NovDecember: 3.42 in precipitation 3.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hamilton Butler Co. Regional Airport, OH (7 mi away); precipitation: Cincinnati 8.9 Nw, OH (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

452186b
Cincinnati, OH · <1 mi
452316b
Cincinnati, OH · 2 mi
452406b
Cincinnati, OH · 2 mi
452466b
Cincinnati, OH · 3 mi
452156b
Cincinnati, OH · 3 mi
452246b
Cincinnati, OH · 4 mi
452166b
Cincinnati, OH · 5 mi
452516b
Cincinnati, OH · 5 mi

All 70 ZIP codes in Cincinnati → · Ohio planting zones →

Questions about 45299

What planting zone is ZIP code 45299?

ZIP code 45299 (Cincinnati, OH) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Cincinnati, OH?

The median last spring frost (32 °F) near 45299 is April 22; after May 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hamilton Butler Co. Regional Airport station.

When is the first frost in Cincinnati, OH?

The median first fall frost near 45299 is October 18, giving a median frost-free growing season of 178 days.

When should I plant tomatoes in 45299?

Start tomato seeds indoors around Feb 25 – Mar 11 and set transplants outside around Apr 29 – May 13, one to three weeks after the median last frost.

How much rain and snow does 45299 get?

About 44.3 inches of precipitation a year (NOAA 1991–2020 normals, Cincinnati 8.9 Nw station).

How hot do summers get in Cincinnati, OH?

The average high peaks at 87 °F in July, with about 28 days a year at 90 °F or more.

What kind of soil does 45299 have?

The USDA soil survey maps Alfic Udarents at the center of ZIP 45299: silty clay loam, moderately well drained, pH about 5.0 (strongly acidic).

Did spring come early in Cincinnati, OH in 2026?

Spring leaf-out near 45299 came on Mar 8 in 2026, 9 days earlier than the 1991–2020 average (Mar 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Cincinnati, OH?

Intermediate onions: the longest day near 45299 is 14 h 56 min, so day-neutral types bulb best; long-day varieties may not bulb fully.