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

Planting zone for 54906 — Oshkosh, WI

ZIP code 54906 (Oshkosh, Winnebago County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is April 24 and the first fall frost October 20.

Where ZIP 54906 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.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostApr 24
First frostOct 20
2012 zone5a

Was 5a 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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Oshkosh, WI…

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 Oshkosh, WI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 24median — 50% chance of a later frost
Safe for tender plantsMay 8only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 4
Growing season178 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 13 and returns around October 31.

From the NOAA station Oshkosh, WI — 6 miles away, elevation 751 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 54906

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 13 – Mar 27
SpinachSow outdoors · Mar 13 – Apr 3
Broccoli, cabbageStart indoors · Feb 13 – Feb 27
Broccoli, cabbageTransplant · Apr 3 – Apr 17
Onion setsPlant outdoors · Mar 27 – Apr 10
PotatoesPlant outdoors · Apr 3 – Apr 17
LettuceSow outdoors · Mar 27 – Apr 10
Carrots, beetsSow outdoors · Apr 3 – Apr 17
TomatoesStart indoors · Feb 27 – Mar 13
TomatoesTransplant · May 1 – May 15
Peppers, eggplantStart indoors · Feb 13 – Feb 27
Peppers, eggplantTransplant · May 8 – May 22
BeansSow outdoors · May 1 – May 15
Sweet cornSow outdoors · May 1 – May 15
Cucumbers, squashSow outdoors · May 1 – May 15
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 24) and first fall frost (Oct 20) 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 54906 came on Apr 10 — 7 days earlier than the 1991–2020 average (Apr 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 5b in Wisconsin

518 plants native to the lower 48 states, recorded in Wisconsin, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Trees 49

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 93

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 hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °F

Wildflowers & perennials 197

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 159

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 sedge4 ft · blooms late 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 °F

Vines 5

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °FVirginia creeper1 ft · blooms late spring · medium shade tolerance · to −28 °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 Oshkosh, WI.

Soil in Oshkosh, WI

The center of ZIP 54906 is mapped as Water: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 54906; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Oshkosh, WI

Summer high82 °Faverage high, July
Winter low10 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights143nights a year at 32 °F or less
Growing degree days2,699base 50 °F — the season’s usable heat
Longest day15 h 30 mindaylight on June 21
Shortest day8 h 53 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation33.3 inper year, rain and melted snow
Snowfall39 inper year; 77 days with snow on the ground

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 26 °F, low 10 °F 26°10° JanFebruary: average high 30 °F, low 13 °F 30°13° FebMarch: average high 41 °F, low 24 °F 41°24° MarApril: average high 54 °F, low 36 °F 54°36° AprMay: average high 67 °F, low 48 °F 67°48° MayJune: average high 77 °F, low 59 °F 77°59° JunJuly: average high 82 °F, low 63 °F 82°63° JulAugust: average high 80 °F, low 61 °F 80°61° AugSeptember: average high 73 °F, low 53 °F 73°53° SepOctober: average high 59 °F, low 41 °F 59°41° OctNovember: average high 44 °F, low 29 °F 44°29° NovDecember: average high 32 °F, low 18 °F 32°18° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 1.34 in precipitation, 9.8 in snowfall 1.3❄10 JanFebruary: 1.11 in precipitation, 10.1 in snowfall 1.1❄10 FebMarch: 1.92 in precipitation, 5.4 in snowfall 1.9❄5 MarApril: 3.21 in precipitation, 1.8 in snowfall 3.2❄2 AprMay: 3.94 in precipitation 3.9 MayJune: 4.82 in precipitation 4.8 JunJuly: 3.76 in precipitation 3.8 JulAugust: 3.40 in precipitation 3.4 AugSeptember: 3.26 in precipitation 3.3 SepOctober: 2.89 in precipitation, 0.3 in snowfall 2.9 OctNovember: 2.05 in precipitation, 1.8 in snowfall 2.0❄2 NovDecember: 1.59 in precipitation, 10 in snowfall 1.6❄10 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Oshkosh, WI (6 mi away); precipitation: Oshkosh, WI (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

549035b
Oshkosh, WI · <1 mi
549275b
Butte Des Morts, WI · 2 mi
549045b
Oshkosh, WI · 3 mi
549015b
Oshkosh, WI · 5 mi
549865b
Winneconne, WI · 6 mi
549855b
Winnebago, WI · 6 mi
549635b
Omro, WI · 6 mi
549805a
Waukau, WI · 8 mi

All 5 ZIP codes in Oshkosh → · Wisconsin planting zones →

Questions about 54906

What planting zone is ZIP code 54906?

ZIP code 54906 (Oshkosh, WI) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Oshkosh, WI?

The median last spring frost (32 °F) near 54906 is April 24; after May 8 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Oshkosh station.

When is the first frost in Oshkosh, WI?

The median first fall frost near 54906 is October 20, giving a median frost-free growing season of 178 days.

When should I plant tomatoes in 54906?

Start tomato seeds indoors around Feb 27 – Mar 13 and set transplants outside around May 1 – May 15, one to three weeks after the median last frost.

How much rain and snow does 54906 get?

About 33.3 inches of precipitation a year and 39 inches of snowfall (NOAA 1991–2020 normals, Oshkosh station).

How hot do summers get in Oshkosh, WI?

The average high peaks at 82 °F in July, with about 8 days a year at 90 °F or more.

Did spring come early in Oshkosh, WI in 2026?

Spring leaf-out near 54906 came on Apr 10 in 2026, 7 days earlier than the 1991–2020 average (Apr 17), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Oshkosh, WI?

Long-day onions: the longest day near 54906 is 15 h 30 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 54906 change?

Yes. The 2012 USDA map put 54906 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.