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

Planting zone for 45883 — Saint Henry, OH

ZIP code 45883 (Saint Henry, Mercer County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 27 and the first fall frost October 19.

Where ZIP 45883 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 27
First frostOct 19
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 Saint Henry, 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 Saint Henry, OH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 27median — 50% chance of a later frost
Safe for tender plantsMay 10only 10% chance of frost after
First fall frostOctober 19median — 10% chance by Oct 3
Growing season175 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 15 and returns around October 31.

From the NOAA station Celina 3 Ne, OH — 12 miles away, elevation 866 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 45883

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 16 – Mar 30
SpinachSow outdoors · Mar 16 – Apr 6
Broccoli, cabbageStart indoors · Feb 16 – Mar 2
Broccoli, cabbageTransplant · Apr 6 – Apr 20
Onion setsPlant outdoors · Mar 30 – Apr 13
PotatoesPlant outdoors · Apr 6 – Apr 20
LettuceSow outdoors · Mar 30 – Apr 13
Carrots, beetsSow outdoors · Apr 6 – Apr 20
TomatoesStart indoors · Mar 2 – Mar 16
TomatoesTransplant · May 4 – May 18
Peppers, eggplantStart indoors · Feb 16 – Mar 2
Peppers, eggplantTransplant · May 11 – May 25
BeansSow outdoors · May 4 – May 18
Sweet cornSow outdoors · May 4 – May 18
Cucumbers, squashSow outdoors · May 4 – May 18
Fall lettuce, spinachSow outdoors · Aug 24 – Sep 7
GarlicPlant cloves · Oct 5 – Nov 9
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 27) and first fall frost (Oct 19) 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 45883 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 Saint Henry, OH

The soil mapped at the center of ZIP 45883 is Blount — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables
pH6.4slightly acidic; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter2%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classPrime farmland if drainedUSDA classification

Map unit: Blount silt loam, end moraine, 2 to 4 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 45883; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Saint Henry, OH

Summer high84 °Faverage high, July
Winter low19 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights116nights a year at 32 °F or less
Growing degree days3,272base 50 °F — the season’s usable heat
Longest day15 h 04 mindaylight on June 21
Shortest day9 h 17 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation38.7 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 34 °F, low 19 °F 34°19° JanFebruary: average high 38 °F, low 22 °F 38°22° FebMarch: average high 49 °F, low 30 °F 49°30° MarApril: average high 63 °F, low 40 °F 63°40° AprMay: average high 73 °F, low 51 °F 73°51° MayJune: average high 81 °F, low 60 °F 81°60° JunJuly: average high 84 °F, low 63 °F 84°63° JulAugust: average high 82 °F, low 61 °F 82°61° AugSeptember: average high 77 °F, low 54 °F 77°54° SepOctober: average high 65 °F, low 44 °F 65°44° OctNovember: average high 50 °F, low 33 °F 50°33° NovDecember: average high 38 °F, low 24 °F 38°24° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.61 in precipitation 2.6 JanFebruary: 2.28 in precipitation 2.3 FebMarch: 2.73 in precipitation 2.7 MarApril: 3.72 in precipitation 3.7 AprMay: 4.08 in precipitation 4.1 MayJune: 4.52 in precipitation 4.5 JunJuly: 4.23 in precipitation 4.2 JulAugust: 3.39 in precipitation 3.4 AugSeptember: 2.86 in precipitation 2.9 SepOctober: 2.82 in precipitation 2.8 OctNovember: 2.77 in precipitation 2.8 NovDecember: 2.67 in precipitation 2.7 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Celina 3 Ne, OH (12 mi away); precipitation: Maria Stein 3.0 Ssw, OH (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

453486a
New Weston, OH · 5 mi
458606a
Maria Stein, OH · 5 mi
453506a
North Star, OH · 6 mi
458286a
Coldwater, OH · 7 mi
458466a
Fort Recovery, OH · 7 mi
458266a
Chickasaw, OH · 7 mi
458666a
Montezuma, OH · 7 mi
453626a
Rossburg, OH · 7 mi

Ohio planting zones →

Questions about 45883

What planting zone is ZIP code 45883?

ZIP code 45883 (Saint Henry, 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 Saint Henry, OH?

The median last spring frost (32 °F) near 45883 is April 27; after May 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Celina 3 Ne station.

When is the first frost in Saint Henry, OH?

The median first fall frost near 45883 is October 19, giving a median frost-free growing season of 175 days.

When should I plant tomatoes in 45883?

Start tomato seeds indoors around Mar 2 – Mar 16 and set transplants outside around May 4 – May 18, one to three weeks after the median last frost.

How much rain and snow does 45883 get?

About 38.7 inches of precipitation a year (NOAA 1991–2020 normals, Maria Stein 3.0 Ssw station).

How hot do summers get in Saint Henry, OH?

The average high peaks at 84 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 45883 have?

The USDA soil survey maps Blount at the center of ZIP 45883: silt loam, somewhat poorly drained, pH about 6.4 (slightly acidic).

Did spring come early in Saint Henry, OH in 2026?

Spring leaf-out near 45883 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 Saint Henry, OH?

Long-day onions: the longest day near 45883 is 15 h 04 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).