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

Planting zone for Waukesha, WI

Waukesha, WI is in USDA zone 5b across its 4 ZIP codes. The median last spring frost is May 1 and the first fall frost October 13.

Waukesha on the zone map

Outlined: its 3 ZIP code areas · 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
ZIP codes4
Last frostMay 1
First frostOct 13
Growing season162 days

5b 4 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

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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 Waukesha, WI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 1median — 50% chance of a later frost
Safe for tender plantsMay 18only 10% chance of frost after
First fall frostOctober 13median — 10% chance by Sep 29
Growing season162 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 19 and returns around October 23.

From the NOAA station Waukesha Wwtp, WI, elevation 791 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 Waukesha

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 20 – Apr 3
SpinachSow outdoors · Mar 20 – Apr 10
Broccoli, cabbageStart indoors · Feb 20 – Mar 6
Broccoli, cabbageTransplant · Apr 10 – Apr 24
Onion setsPlant outdoors · Apr 3 – Apr 17
PotatoesPlant outdoors · Apr 10 – Apr 24
LettuceSow outdoors · Apr 3 – Apr 17
Carrots, beetsSow outdoors · Apr 10 – Apr 24
TomatoesStart indoors · Mar 6 – Mar 20
TomatoesTransplant · May 8 – May 22
Peppers, eggplantStart indoors · Feb 20 – Mar 6
Peppers, eggplantTransplant · May 15 – May 29
BeansSow outdoors · May 8 – May 22
Sweet cornSow outdoors · May 8 – May 22
Cucumbers, squashSow outdoors · May 8 – May 22
Fall lettuce, spinachSow outdoors · Aug 18 – Sep 1
GarlicPlant cloves · Sep 29 – Nov 3
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 1) and first fall frost (Oct 13) 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 53187 came on Mar 30 — 13 days earlier than the 1991–2020 average (Apr 12).

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 Waukesha, WI.

Soil in Waukesha, WI

The soil mapped at the center of ZIP 53187 is Pella, poorly drained.

DrainagePoorly drainedconsider raised beds
Farmland classNot prime farmlandUSDA classification

Map unit: Loamy land.

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 53187; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Waukesha, WI

Summer high81 °Faverage high, July
Winter low12 °Faverage low, January
Hot days11days a year at 90 °F or more
Freezing nights143nights a year at 32 °F or less
Growing degree days2,535base 50 °F — the season’s usable heat
Longest day15 h 22 mindaylight on June 21
Shortest day9 h 00 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation36 inper year, rain and melted snow
Snowfall37 inper year; 62 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 28 °F, low 12 °F 28°12° JanFebruary: average high 32 °F, low 15 °F 32°15° FebMarch: average high 43 °F, low 24 °F 43°24° MarApril: average high 55 °F, low 35 °F 55°35° AprMay: average high 67 °F, low 46 °F 67°46° MayJune: average high 77 °F, low 56 °F 77°56° JunJuly: average high 81 °F, low 60 °F 81°60° JulAugust: average high 80 °F, low 59 °F 80°59° AugSeptember: average high 73 °F, low 51 °F 73°51° SepOctober: average high 60 °F, low 40 °F 60°40° OctNovember: average high 45 °F, low 28 °F 45°28° NovDecember: average high 33 °F, low 18 °F 33°18° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 1.60 in precipitation, 10.4 in snowfall 1.6❄10 JanFebruary: 1.71 in precipitation, 10.1 in snowfall 1.7❄10 FebMarch: 1.93 in precipitation, 4.6 in snowfall 1.9❄5 MarApril: 3.65 in precipitation, 1.1 in snowfall 3.6❄1 AprMay: 3.97 in precipitation 4.0 MayJune: 4.88 in precipitation 4.9 JunJuly: 3.99 in precipitation 4.0 JulAugust: 4.18 in precipitation 4.2 AugSeptember: 3.27 in precipitation 3.3 SepOctober: 2.92 in precipitation, 0.1 in snowfall 2.9 OctNovember: 2.15 in precipitation, 1.8 in snowfall 2.1❄2 NovDecember: 1.70 in precipitation, 8.8 in snowfall 1.7❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Waukesha Wwtp, WI (within 1 mile); precipitation: Waukesha Wwtp, WI (within 1 mile). Daylight is calculated from latitude.

ZIP codes in Waukesha

531865b
−15 to −10 °F
531875b
−15 to −10 °F
531885b
−15 to −10 °F
531895b
−15 to −10 °F

Wisconsin planting zones →

Questions about Waukesha

What planting zone is Waukesha, WI?

Waukesha, WI is in USDA hardiness zone 5b on the 2023 map (5b: −15 to −10 °F).

When is the last frost in Waukesha, WI?

The median last spring frost is May 1 and the median first fall frost is October 13 (NOAA 1991–2020 normals, Waukesha Wwtp station).

When can I plant a garden in Waukesha, WI?

Cool-season crops like peas and spinach go in around Mar 20 – Apr 10; tomatoes, peppers, beans and squash after about May 8, once frost risk has passed.

What kind of onions grow in Waukesha, WI?

Long-day onions: the longest day is 15 h 22 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

How much rain and snow does Waukesha, WI get?

About 36 inches of precipitation a year and 37 inches of snowfall (NOAA 1991–2020 normals).