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

Planting zone for 45370 — Spring Valley, OH

ZIP code 45370 (Spring Valley, Greene County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 18 and the first fall frost October 24.

Where ZIP 45370 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 18
First frostOct 24
2012 zone6a

Was 6a on the 2012 map — half a zone warmer now. 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 Spring Valley, 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 Spring Valley, OH

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 18median — 50% chance of a later frost
Safe for tender plantsMay 4only 10% chance of frost after
First fall frostOctober 24median — 10% chance by Oct 11
Growing season188 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 5 and returns around November 3.

From the NOAA station Xenia 6 Sse, OH — 7 miles away, elevation 997 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 45370

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 7 – Mar 21
SpinachSow outdoors · Mar 7 – Mar 28
Broccoli, cabbageStart indoors · Feb 7 – Feb 21
Broccoli, cabbageTransplant · Mar 28 – Apr 11
Onion setsPlant outdoors · Mar 21 – Apr 4
PotatoesPlant outdoors · Mar 28 – Apr 11
LettuceSow outdoors · Mar 21 – Apr 4
Carrots, beetsSow outdoors · Mar 28 – Apr 11
TomatoesStart indoors · Feb 21 – Mar 7
TomatoesTransplant · Apr 25 – May 9
Peppers, eggplantStart indoors · Feb 7 – Feb 21
Peppers, eggplantTransplant · May 2 – May 16
BeansSow outdoors · Apr 25 – May 9
Sweet cornSow outdoors · Apr 25 – May 9
Cucumbers, squashSow outdoors · Apr 25 – May 9
Fall lettuce, spinachSow outdoors · Aug 29 – Sep 12
GarlicPlant cloves · Oct 10 – Nov 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 24) 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 45370 came on Mar 10 — 13 days earlier than the 1991–2020 average (Mar 23).

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 Spring Valley, OH.

Soil in Spring Valley, OH

The soil mapped at the center of ZIP 45370 is Eldean — 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 groupBwater soaks in moderately
Farmland classFarmland of local importanceUSDA classification

Map unit: Eldean silt loam, 6 to 12 percent slopes, moderately eroded.

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 45370; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Spring Valley, OH

Summer high83 °Faverage high, July
Winter low23 °Faverage low, January
Hot days9days a year at 90 °F or more
Freezing nights104nights a year at 32 °F or less
Growing degree days3,573base 50 °F — the season’s usable heat
Longest day14 h 58 mindaylight on June 21
Shortest day9 h 22 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation43 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 38 °F, low 23 °F 38°23° JanFebruary: average high 42 °F, low 25 °F 42°25° FebMarch: average high 52 °F, low 34 °F 52°34° MarApril: average high 65 °F, low 44 °F 65°44° AprMay: average high 73 °F, low 54 °F 73°54° MayJune: average high 81 °F, low 62 °F 81°62° JunJuly: average high 83 °F, low 65 °F 83°65° JulAugust: average high 82 °F, low 63 °F 82°63° AugSeptember: average high 77 °F, low 56 °F 77°56° SepOctober: average high 66 °F, low 46 °F 66°46° OctNovember: average high 53 °F, low 36 °F 53°36° NovDecember: average high 42 °F, low 28 °F 42°28° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.27 in precipitation 3.3 JanFebruary: 2.73 in precipitation 2.7 FebMarch: 3.68 in precipitation 3.7 MarApril: 4.48 in precipitation 4.5 AprMay: 4.51 in precipitation 4.5 MayJune: 4.58 in precipitation 4.6 JunJuly: 3.99 in precipitation 4.0 JulAugust: 3.17 in precipitation 3.2 AugSeptember: 3.07 in precipitation 3.1 SepOctober: 3.10 in precipitation 3.1 OctNovember: 3.08 in precipitation 3.1 NovDecember: 3.34 in precipitation 3.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Xenia 6 Sse, OH (7 mi away); precipitation: Centerville 3.9 S, OH (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

453056b
Bellbrook, OH · 4 mi
450686b
Waynesville, OH · 5 mi
454406b
Dayton, OH · 6 mi
454586b
Dayton, OH · 7 mi
450326b
Harveysburg, OH · 7 mi
453856b
Xenia, OH · 8 mi
454596b
Dayton, OH · 8 mi
454346b
Dayton, OH · 8 mi

Ohio planting zones →

Questions about 45370

What planting zone is ZIP code 45370?

ZIP code 45370 (Spring Valley, 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 Spring Valley, OH?

The median last spring frost (32 °F) near 45370 is April 18; after May 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Xenia 6 Sse station.

When is the first frost in Spring Valley, OH?

The median first fall frost near 45370 is October 24, giving a median frost-free growing season of 188 days.

When should I plant tomatoes in 45370?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 45370 get?

About 43 inches of precipitation a year (NOAA 1991–2020 normals, Centerville 3.9 S station).

How hot do summers get in Spring Valley, OH?

The average high peaks at 83 °F in July, with about 9 days a year at 90 °F or more.

What kind of soil does 45370 have?

The USDA soil survey maps Eldean at the center of ZIP 45370: silt loam, well drained, pH about 6.5 (neutral).

Did spring come early in Spring Valley, OH in 2026?

Spring leaf-out near 45370 came on Mar 10 in 2026, 13 days earlier than the 1991–2020 average (Mar 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Spring Valley, OH?

Intermediate onions: the longest day near 45370 is 14 h 58 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 45370 change?

Yes. The 2012 USDA map put 45370 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.