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

Planting zone for 53518 — Blue River, WI

ZIP code 53518 (Blue River, Grant County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 3 and the first fall frost October 7.

Where ZIP 53518 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.

Zone5a−20 to −15 °F
Coldest night−28.9 to −26.1 °C
Last frostMay 3
First frostOct 7
2012 zone5a

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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Blue River, 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 Blue River, WI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 3median — 50% chance of a later frost
Safe for tender plantsMay 18only 10% chance of frost after
First fall frostOctober 7median — 10% chance by Sep 25
Growing season155 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 22 and returns around October 17.

From the NOAA station Boscobel Airport, WI — 7 miles away, elevation 673 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 53518

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 22 – Apr 5
SpinachSow outdoors · Mar 22 – Apr 12
Broccoli, cabbageStart indoors · Feb 22 – Mar 8
Broccoli, cabbageTransplant · Apr 12 – Apr 26
Onion setsPlant outdoors · Apr 5 – Apr 19
PotatoesPlant outdoors · Apr 12 – Apr 26
LettuceSow outdoors · Apr 5 – Apr 19
Carrots, beetsSow outdoors · Apr 12 – Apr 26
TomatoesStart indoors · Mar 8 – Mar 22
TomatoesTransplant · May 10 – May 24
Peppers, eggplantStart indoors · Feb 22 – Mar 8
Peppers, eggplantTransplant · May 17 – May 31
BeansSow outdoors · May 10 – May 24
Sweet cornSow outdoors · May 10 – May 24
Cucumbers, squashSow outdoors · May 10 – May 24
Fall lettuce, spinachSow outdoors · Aug 12 – Aug 26
GarlicPlant cloves · Sep 23 – Oct 28
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 3) and first fall frost (Oct 7) 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 53518 came on Mar 30 — 14 days earlier than the 1991–2020 average (Apr 13).

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 5a in Wisconsin

510 plants native to the lower 48 states, recorded in Wisconsin, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

Trees 48

Shrubs 93

Wildflowers & perennials 191

Grasses 158

Vines 5

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 Blue River, WI.

Soil in Blue River, WI

The soil mapped at the center of ZIP 53518 is Dorerton — loam, well drained.

TextureLoama good balance for most vegetables
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter5%high
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Dorerton, very stony-Elbaville complex, 30 to 60 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 53518; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Blue River, WI

Summer high84 °Faverage high, July
Winter low10 °Faverage low, January
Hot days19days a year at 90 °F or more
Freezing nights152nights a year at 32 °F or less
Growing degree days2,891base 50 °F — the season’s usable heat
Longest day15 h 23 mindaylight on June 21
Shortest day8 h 58 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation33.9 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 29 °F, low 10 °F 29°10° JanFebruary: average high 34 °F, low 14 °F 34°14° FebMarch: average high 47 °F, low 25 °F 47°25° MarApril: average high 61 °F, low 36 °F 61°36° AprMay: average high 72 °F, low 47 °F 72°47° MayJune: average high 81 °F, low 57 °F 81°57° JunJuly: average high 84 °F, low 61 °F 84°61° JulAugust: average high 83 °F, low 59 °F 83°59° AugSeptember: average high 76 °F, low 51 °F 76°51° SepOctober: average high 63 °F, low 38 °F 63°38° OctNovember: average high 47 °F, low 28 °F 47°28° NovDecember: average high 34 °F, low 17 °F 34°17° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 0.98 in precipitation 1.0 JanFebruary: 0.96 in precipitation 1.0 FebMarch: 1.91 in precipitation 1.9 MarApril: 3.64 in precipitation 3.6 AprMay: 4.35 in precipitation 4.3 MayJune: 5.15 in precipitation 5.2 JunJuly: 3.84 in precipitation 3.8 JulAugust: 4.07 in precipitation 4.1 AugSeptember: 3.37 in precipitation 3.4 SepOctober: 2.48 in precipitation 2.5 OctNovember: 1.87 in precipitation 1.9 NovDecember: 1.32 in precipitation 1.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Boscobel Airport, WI (7 mi away); precipitation: Boscobel Airport, WI (7 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.

Wisconsin planting zones →

Questions about 53518

What planting zone is ZIP code 53518?

ZIP code 53518 (Blue River, WI) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Blue River, WI?

The median last spring frost (32 °F) near 53518 is May 3; after May 18 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Boscobel Airport station.

When is the first frost in Blue River, WI?

The median first fall frost near 53518 is October 7, giving a median frost-free growing season of 155 days.

When should I plant tomatoes in 53518?

Start tomato seeds indoors around Mar 8 – Mar 22 and set transplants outside around May 10 – May 24, one to three weeks after the median last frost.

How much rain and snow does 53518 get?

About 33.9 inches of precipitation a year (NOAA 1991–2020 normals, Boscobel Airport station).

How hot do summers get in Blue River, WI?

The average high peaks at 84 °F in July, with about 19 days a year at 90 °F or more.

What kind of soil does 53518 have?

The USDA soil survey maps Dorerton at the center of ZIP 53518: loam, well drained, pH about 5.8 (moderately acidic).

Did spring come early in Blue River, WI in 2026?

Spring leaf-out near 53518 came on Mar 30 in 2026, 14 days earlier than the 1991–2020 average (Apr 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Blue River, WI?

Long-day onions: the longest day near 53518 is 15 h 23 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).