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

Planting zone for 54023 — Roberts, WI

ZIP code 54023 (Roberts, St. Croix County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 6 and the first fall frost October 2.

Where ZIP 54023 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.

Zone4b−25 to −20 °F
Coldest night−31.7 to −28.9 °C
Last frostMay 6
First frostOct 2
2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Roberts, 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 Roberts, WI

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 6median — 50% chance of a later frost
Safe for tender plantsMay 21only 10% chance of frost after
First fall frostOctober 2median — 10% chance by Sep 18
Growing season148 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 26 and returns around October 12.

From the NOAA station Baldwin, WI — 7 miles away, elevation 1,099 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 54023

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 25 – Apr 8
SpinachSow outdoors · Mar 25 – Apr 15
Broccoli, cabbageStart indoors · Feb 25 – Mar 11
Broccoli, cabbageTransplant · Apr 15 – Apr 29
Onion setsPlant outdoors · Apr 8 – Apr 22
PotatoesPlant outdoors · Apr 15 – Apr 29
LettuceSow outdoors · Apr 8 – Apr 22
Carrots, beetsSow outdoors · Apr 15 – Apr 29
TomatoesStart indoors · Mar 11 – Mar 25
TomatoesTransplant · May 13 – May 27
Peppers, eggplantStart indoors · Feb 25 – Mar 11
Peppers, eggplantTransplant · May 20 – Jun 3
BeansSow outdoors · May 13 – May 27
Sweet cornSow outdoors · May 13 – May 27
Cucumbers, squashSow outdoors · May 13 – May 27
Fall lettuce, spinachSow outdoors · Aug 7 – Aug 21
GarlicPlant cloves · Sep 18 – Oct 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 6) and first fall frost (Oct 2) 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 54023 came on Apr 11 — 7 days earlier than the 1991–2020 average (Apr 18).

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).

Soil in Roberts, WI

The soil mapped at the center of ZIP 54023 is Lawler — silt loam, somewhat poorly drained.

TextureSilt loama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainageSomewhat poorly drainedconsider raised beds
Organic matter4.5%moderate
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classprime farmlandUSDA classification

Map unit: Lawler silt loam, 0 to 3 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 54023; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Roberts, WI

Summer high79 °Faverage high, July
Winter low2 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights170nights a year at 32 °F or less
Growing degree days2,241base 50 °F — the season’s usable heat
Longest day15 h 37 mindaylight on June 21
Shortest day8 h 46 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation32.8 inper year, rain and melted snow
Snowfall50 inper year

Average high and low, by month

−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 20 °F, low 2 °F 20°2° JanFebruary: average high 26 °F, low 5 °F 26°5° FebMarch: average high 37 °F, low 19 °F 37°19° MarApril: average high 54 °F, low 33 °F 54°33° AprMay: average high 66 °F, low 45 °F 66°45° MayJune: average high 76 °F, low 56 °F 76°56° JunJuly: average high 79 °F, low 59 °F 79°59° JulAugust: average high 77 °F, low 57 °F 77°57° AugSeptember: average high 71 °F, low 49 °F 71°49° SepOctober: average high 56 °F, low 36 °F 56°36° OctNovember: average high 40 °F, low 23 °F 40°23° NovDecember: average high 27 °F, low 10 °F 27°10° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 0.72 in precipitation, 8.1 in snowfall 0.7❄8 JanFebruary: 0.57 in precipitation, 12.6 in snowfall 0.6❄13 FebMarch: 1.47 in precipitation, 6.9 in snowfall 1.5❄7 MarApril: 3.10 in precipitation, 4.7 in snowfall 3.1❄5 AprMay: 4.15 in precipitation, 0.8 in snowfall 4.2❄1 MayJune: 5.35 in precipitation 5.3 JunJuly: 4.42 in precipitation 4.4 JulAugust: 4.08 in precipitation 4.1 AugSeptember: 3.47 in precipitation 3.5 SepOctober: 2.86 in precipitation, 0.6 in snowfall 2.9❄1 OctNovember: 1.50 in precipitation, 2.3 in snowfall 1.5❄2 NovDecember: 1.08 in precipitation, 13.7 in snowfall 1.1❄14 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Baldwin, WI (7 mi away); precipitation: Roberts Wwtp, WI (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

540154b
Hammond, WI · 5 mi
540164b
Hudson, WI · 7 mi
540024b
Baldwin, WI · 9 mi
540224b
River Falls, WI · 10 mi
540174b
New Richmond, WI · 10 mi
550435a
Lakeland, MN · 11 mi
550035a
Bayport, MN · 11 mi
540824b
Houlton, WI · 12 mi

Wisconsin planting zones →

Questions about 54023

What planting zone is ZIP code 54023?

ZIP code 54023 (Roberts, WI) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Roberts, WI?

The median last spring frost (32 °F) near 54023 is May 6; after May 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Baldwin station.

When is the first frost in Roberts, WI?

The median first fall frost near 54023 is October 2, giving a median frost-free growing season of 148 days.

When should I plant tomatoes in 54023?

Start tomato seeds indoors around Mar 11 – Mar 25 and set transplants outside around May 13 – May 27, one to three weeks after the median last frost.

How much rain and snow does 54023 get?

About 32.8 inches of precipitation a year and 50 inches of snowfall (NOAA 1991–2020 normals, Roberts Wwtp station).

How hot do summers get in Roberts, WI?

The average high peaks at 79 °F in July, with about 4 days a year at 90 °F or more.

What kind of soil does 54023 have?

The USDA soil survey maps Lawler at the center of ZIP 54023: silt loam, somewhat poorly drained, pH about 6.5 (neutral).

Did spring come early in Roberts, WI in 2026?

Spring leaf-out near 54023 came on Apr 11 in 2026, 7 days earlier than the 1991–2020 average (Apr 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Roberts, WI?

Long-day onions: the longest day near 54023 is 15 h 37 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).