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

Planting zone for 54532 — Heafford Junction, WI

ZIP code 54532 (Heafford Junction, Lincoln County) is in USDA zone 4a: the coldest winter night averages −30 to −25 °F. The median last spring frost is May 10 and the first fall frost October 4.

Where ZIP 54532 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.

Zone4a−30 to −25 °F
Coldest night−34.4 to −31.7 °C
Last frostMay 10
First frostOct 4
2012 zone4a

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 4a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Heafford Junction, 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 Heafford Junction, WI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 10median — 50% chance of a later frost
Safe for tender plantsMay 27only 10% chance of frost after
First fall frostOctober 4median — 10% chance by Sep 21
Growing season146 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 16.

From the NOAA station Rice Rsvr Tomahawk-2, WI — within 1 mile, elevation 1,460 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 54532

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 29 – Apr 12
SpinachSow outdoors · Mar 29 – Apr 19
Broccoli, cabbageStart indoors · Mar 1 – Mar 15
Broccoli, cabbageTransplant · Apr 19 – May 3
Onion setsPlant outdoors · Apr 12 – Apr 26
PotatoesPlant outdoors · Apr 19 – May 3
LettuceSow outdoors · Apr 12 – Apr 26
Carrots, beetsSow outdoors · Apr 19 – May 3
TomatoesStart indoors · Mar 15 – Mar 29
TomatoesTransplant · May 17 – May 31
Peppers, eggplantStart indoors · Mar 1 – Mar 15
Peppers, eggplantTransplant · May 24 – Jun 7
BeansSow outdoors · May 17 – May 31
Sweet cornSow outdoors · May 17 – May 31
Cucumbers, squashSow outdoors · May 17 – May 31
Fall lettuce, spinachSow outdoors · Aug 9 – Aug 23
GarlicPlant cloves · Sep 20 – Oct 25
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 10) and first fall frost (Oct 4) 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 54532 came on Apr 17 — 8 days earlier than the 1991–2020 average (Apr 25).

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 4a in Wisconsin

419 plants native to the lower 48 states, recorded in Wisconsin, and rated by the USDA to survive −30 °F or colder — the bottom of zone 4a. Each links to its USDA PLANTS profile.

Trees 45

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 71

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 157

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 133

arctic 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 °FBebb's sedge3 ft · blooms late spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °F

Vines 3

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 °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 Heafford Junction, WI.

Soil in Heafford Junction, WI

The soil mapped at the center of ZIP 54532 is Vilas — loamy sand, excessively drained.

TextureLoamy sanddrains and warms fast; dries out and needs more feeding
pH5.5moderately acidic; most vegetables like 6.0–7.0
DrainageExcessively drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Vilas-Sayner loamy sands, 1 to 6 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 54532; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Heafford Junction, WI

Summer high77 °Faverage high, July
Winter low2 °Faverage low, January
Hot days1days a year at 90 °F or more
Freezing nights177nights a year at 32 °F or less
Growing degree days1,853base 50 °F — the season’s usable heat
Longest day15 h 41 mindaylight on June 21
Shortest day8 h 42 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation31.5 inper year, rain and melted snow

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 21 °F, low 2 °F 21°2° JanFebruary: average high 26 °F, low 3 °F 26°3° FebMarch: average high 37 °F, low 15 °F 37°15° MarApril: average high 50 °F, low 29 °F 50°29° AprMay: average high 64 °F, low 43 °F 64°43° MayJune: average high 73 °F, low 53 °F 73°53° JunJuly: average high 77 °F, low 57 °F 77°57° JulAugust: average high 74 °F, low 55 °F 74°55° AugSeptember: average high 66 °F, low 48 °F 66°48° SepOctober: average high 53 °F, low 36 °F 53°36° OctNovember: average high 38 °F, low 23 °F 38°23° NovDecember: average high 26 °F, low 11 °F 26°11° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 1.18 in precipitation 1.2 JanFebruary: 1.08 in precipitation 1.1 FebMarch: 1.81 in precipitation 1.8 MarApril: 2.86 in precipitation 2.9 AprMay: 3.60 in precipitation 3.6 MayJune: 4.16 in precipitation 4.2 JunJuly: 3.68 in precipitation 3.7 JulAugust: 3.43 in precipitation 3.4 AugSeptember: 3.57 in precipitation 3.6 SepOctober: 2.96 in precipitation 3.0 OctNovember: 1.76 in precipitation 1.8 NovDecember: 1.44 in precipitation 1.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Rice Rsvr Tomahawk-2, WI (within 1 mile); precipitation: Rice Rsvr Tomahawk-2, WI (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

544874a
Tomahawk, WI · 3 mi
545294a
Harshaw, WI · 9 mi
545644a
Tripoli, WI · 13 mi
544424b
Irma, WI · 13 mi
545434b
Mc Naughton, WI · 14 mi
545314a
Hazelhurst, WI · 14 mi
544354b
Gleason, WI · 19 mi
545014b
Rhinelander, WI · 19 mi

Wisconsin planting zones →

Questions about 54532

What planting zone is ZIP code 54532?

ZIP code 54532 (Heafford Junction, WI) is in USDA hardiness zone 4a on the 2023 map: the coldest night of an average winter reaches −30 to −25 °F (−34.4 to −31.7 °C).

When is the last frost in Heafford Junction, WI?

The median last spring frost (32 °F) near 54532 is May 10; after May 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Rice Rsvr Tomahawk-2 station.

When is the first frost in Heafford Junction, WI?

The median first fall frost near 54532 is October 4, giving a median frost-free growing season of 146 days.

When should I plant tomatoes in 54532?

Start tomato seeds indoors around Mar 15 – Mar 29 and set transplants outside around May 17 – May 31, one to three weeks after the median last frost.

How much rain and snow does 54532 get?

About 31.5 inches of precipitation a year (NOAA 1991–2020 normals, Rice Rsvr Tomahawk-2 station).

How hot do summers get in Heafford Junction, WI?

The average high peaks at 77 °F in July, with about 1 days a year at 90 °F or more.

What kind of soil does 54532 have?

The USDA soil survey maps Vilas at the center of ZIP 54532: loamy sand, excessively drained, pH about 5.5 (moderately acidic).

Did spring come early in Heafford Junction, WI in 2026?

Spring leaf-out near 54532 came on Apr 17 in 2026, 8 days earlier than the 1991–2020 average (Apr 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Heafford Junction, WI?

Long-day onions: the longest day near 54532 is 15 h 41 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).