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

Planting zone for 45503 — Springfield, OH

ZIP code 45503 (Springfield, Clark 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 19.

Where ZIP 45503 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 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 Springfield, 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 Springfield, 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 12only 10% chance of frost after
First fall frostOctober 19median — 10% chance by Oct 4
Growing season175 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 15 and returns around October 30.

From the NOAA station Springfield Wtp, OH — 2 miles away, elevation 951 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 45503

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 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 25) 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 45503 came on Mar 10 — 18 days earlier than the 1991–2020 average (Mar 28).

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 Springfield, OH.

Soil in Springfield, OH

The soil mapped at the center of ZIP 45503 is Miamian — 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 classNot prime farmlandUSDA classification

Map unit: Miamian-Urban land complex, 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 45503; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Springfield, OH

Summer high84 °Faverage high, July
Winter low19 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights126nights a year at 32 °F or less
Growing degree days3,154base 50 °F — the season’s usable heat
Longest day15 h 01 mindaylight on June 21
Shortest day9 h 20 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation40.3 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 36 °F, low 19 °F 36°19° JanFebruary: average high 40 °F, low 20 °F 40°20° FebMarch: average high 50 °F, low 28 °F 50°28° MarApril: average high 63 °F, low 38 °F 63°38° AprMay: average high 73 °F, low 49 °F 73°49° MayJune: average high 81 °F, low 59 °F 81°59° JunJuly: average high 84 °F, low 62 °F 84°62° JulAugust: average high 83 °F, low 60 °F 83°60° AugSeptember: average high 78 °F, low 52 °F 78°52° SepOctober: average high 65 °F, low 41 °F 65°41° OctNovember: average high 52 °F, low 31 °F 52°31° NovDecember: average high 41 °F, low 24 °F 41°24° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.69 in precipitation 2.7 JanFebruary: 2.10 in precipitation 2.1 FebMarch: 2.94 in precipitation 2.9 MarApril: 3.96 in precipitation 4.0 AprMay: 4.59 in precipitation 4.6 MayJune: 4.48 in precipitation 4.5 JunJuly: 4.55 in precipitation 4.5 JulAugust: 3.28 in precipitation 3.3 AugSeptember: 3.39 in precipitation 3.4 SepOctober: 2.83 in precipitation 2.8 OctNovember: 2.80 in precipitation 2.8 NovDecember: 2.64 in precipitation 2.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Springfield Wtp, OH (2 mi away); precipitation: Springfield Wtp, OH (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

455016a
Springfield, OH · 3 mi
455056a
Springfield, OH · 4 mi
453726a
Tremont City, OH · 5 mi
455046a
Springfield, OH · 5 mi
455066a
Springfield, OH · 5 mi
455026a
Springfield, OH · 7 mi
430106a
Catawba, OH · 8 mi
453696a
South Vienna, OH · 9 mi

All 6 ZIP codes in Springfield → · Ohio planting zones →

Questions about 45503

What planting zone is ZIP code 45503?

ZIP code 45503 (Springfield, 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 Springfield, OH?

The median last spring frost (32 °F) near 45503 is April 25; after May 12 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Springfield Wtp station.

When is the first frost in Springfield, OH?

The median first fall frost near 45503 is October 19, giving a median frost-free growing season of 175 days.

When should I plant tomatoes in 45503?

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 45503 get?

About 40.3 inches of precipitation a year (NOAA 1991–2020 normals, Springfield Wtp station).

How hot do summers get in Springfield, 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 45503 have?

The USDA soil survey maps Miamian at the center of ZIP 45503: silt loam, well drained, pH about 6.5 (neutral).

Did spring come early in Springfield, OH in 2026?

Spring leaf-out near 45503 came on Mar 10 in 2026, 18 days earlier than the 1991–2020 average (Mar 28), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Springfield, OH?

Long-day onions: the longest day near 45503 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).