USDA zone 4b in Wisconsin
USDA plant hardiness zone 4b covers 63 locations across Wisconsin (average annual extreme minimum −25 to −20 °F): Abbotsford, WI, Antigo, WI, Arkansaw, WI, Augusta, WI, Baldwin, WI, Balsam Lake, WI, and 57 more. Average last spring frost across this group ranges April 22 (Houlton) to June 4 (Long Lake), and growing seasons run 95–180 days (Long Lake to Fountain) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Wisconsin location's own frost dates; the printable planting calendar uses Independence, this group's median-season location.
- USDA zone
- 4b−25 to −20 °F
- Last frost range
- Apr 22–Jun 4avg, 32°F
- First frost range
- Sep 10–Oct 21avg, 32°F
- Growing season range
- 95–180days
Locations in this group
Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.
| Location | Also covers | Nearest station | Last frost | First frost | Season (days) |
|---|---|---|---|---|---|
| Abbotsford | Athens, Dorchester, Stetsonville | Medford | May 11 | Oct 1 | 141 |
| Antigo | White Lake, Mattoon, Summit Lake | Antigo | May 14 | Sep 30 | 139 |
| Arkansaw | — | Durand | May 1 | Oct 10 | 162 |
| Augusta | Osseo, Fairchild | Augusta Rs | May 7 | Oct 1 | 146 |
| Baldwin | Woodville | Baldwin | May 6 | Oct 2 | 148 |
| Balsam Lake | Luck, Milltown, Centuria, Lewis | Luck | May 6 | Oct 4 | 149 |
| Bancroft | Plainfield, Coloma, Almond, Hancock | Hancock Exp Farm | May 10 | Oct 3 | 146 |
| Birch Hill | — | Saxon 1wsw | May 23 | Oct 1 | 132 |
| Birnamwood | Wittenberg, Mattoon, Elderon, Rosholt, Hatley | Rosholt 9 Nne | May 6 | Oct 5 | 150 |
| Black River Falls | Neillsville, Fairchild, Hatfield, Humbird, Alma Center, Granton | Neillsville 3ese | May 10 | Oct 1 | 144 |
| Blair | Whitehall, Hixton, Melrose, Ettrick, Taylor, Pigeon Falls | Blair | May 9 | Oct 1 | 143 |
| Bowler | — | Stockbridge-munsee Rsvn | May 13 | Sep 30 | 141 |
| Boyceville | Downing, Dallas, Prairie Farm, Wheeler, Ridgeland | Ridgeland 1nne | May 10 | Sep 29 | 140 |
| Bruce | — | Weyerhaeuser 1n | May 9 | Sep 29 | 140 |
| Cornell | Holcombe, Conrath | Holcombe | May 5 | Oct 2 | 149 |
| Cornucopia | — | Madeline Island | May 20 | Oct 9 | 140 |
| Cumberland | Turtle Lake, Almena, Barronett | Cumberland | May 5 | Oct 4 | 152 |
| Eagle River | Three Lakes, Sayner | Eagle Rvr | May 25 | Sep 24 | 121 |
| Eau Claire | Chippewa Falls, Elk Mound, Fall Creek | Eau Claire Rgnl Ap | May 8 | Oct 4 | 149 |
| Fountain | Arcadia, Dodge, Rollingstone | Winona Dam 5 A | Apr 23 | Oct 21 | 180 |
| Galesville | — | Trempealeau Dam 6 | Apr 29 | Oct 11 | 165 |
| Goodman | Amberg, Crivitz, Wausaukee | Crivitz High Falls | May 26 | Sep 22 | 118 |
| Goodman | Dunbar | Goodman Sanitary Dist | May 24 | Sep 30 | 128 |
| Grand Marsh | Easton, Friendship | Friendship | May 9 | Oct 3 | 147 |
| Grand View | — | Drummond | May 20 | Oct 1 | 132 |
| Greenwood | Owen, Colby, Loyal, Unity, Curtiss | Owen 1e | May 13 | Sep 26 | 136 |
| Herbster | — | Port Wing | May 31 | Oct 2 | 123 |
| Houlton | — | Stillwater 1 Se | Apr 22 | Oct 19 | 178 |
| Hurley | — | Hurley | May 24 | Sep 28 | 128 |
| Independence * | Mondovi, Durand, Strum, Eleva | Mondovi | May 10 | Oct 2 | 144 |
| Jolmaville | Marengo | Mellen 4 Ne | May 26 | Sep 27 | 125 |
| La Farge | — | Viroqua | May 7 | Oct 2 | 148 |
| Lake Arrowhead | Port Edwards, Lake Wazeecha, Nekoosa, Rudolph, Vesper | Wisconsin Rapids Alexander Fld | May 8 | Oct 1 | 145 |
| Lakewood | — | Lakewood 3 Ne | May 22 | Sep 28 | 129 |
| Long Lake | — | Stambaugh 2sse | Jun 4 | Sep 10 | 95 |
| Maine | Weston, Wausau, Marathon, Aniwa, Edgar, Hatley | Wausau Dwtn Ap | May 6 | Oct 4 | 150 |
| Marshfield | Stratford, Auburndale, Spencer, Chili, Milladore, Hewitt, +1 more | Marshfield Exp Farm | May 5 | Oct 5 | 150 |
| Menomonie | Wilson, Knapp, Elmwood, Downsville | Menomonie | May 9 | Oct 1 | 143 |
| Mountain | Green Valley | Suring | May 14 | Oct 1 | 139 |
| Necedah | Arkdale, Camp Douglas | Necedah | May 17 | Sep 25 | 131 |
| Neopit | — | Shawano 2ssw | May 9 | Oct 2 | 144 |
| New Auburn | Bloomer, Colfax, Jim Falls | Bloomer | May 5 | Oct 3 | 151 |
| New Lisbon | Hustler | Mauston 1 Se | May 2 | Oct 7 | 158 |
| New Richmond | Clayton, Amery, Clear Lake, Star Prairie, Emerald, Deer Park | Amery | May 5 | Oct 4 | 151 |
| Ontario | — | Cashton | Apr 27 | Oct 14 | 170 |
| Osceola | Dresser, Shafer | St Croix Falls | May 4 | Oct 8 | 156 |
| Poplar | — | Brule Rs | May 24 | Sep 26 | 124 |
| Post Lake | Crandon, Mole Lake, Wabeno, White Lake, Laona, Newald, +1 more | Laona 6 Sw | May 19 | Sep 29 | 131 |
| Prescott | — | Hastings Dam 2 | Apr 23 | Oct 19 | 177 |
| Rhinelander | Elcho, Summit Lake | Rhinelander | May 22 | Sep 24 | 125 |
| Rice Lake | Barron, Cameron, Chetek | Rice Lake | May 8 | Oct 2 | 145 |
| River Falls | Hudson, Roberts, Hammond | River Falls | May 11 | Oct 1 | 143 |
| Sayner | Woodruff | Minocqua | May 23 | Sep 27 | 127 |
| Sextonville | Gotham | Richland Ctr | May 5 | Oct 6 | 154 |
| Sparta | Rockland, Mindoro | Sparta | May 9 | Oct 1 | 144 |
| Spring Valley | Ellsworth, Plum, Bay | Ellsworth 1e | May 13 | Sep 29 | 139 |
| Stanley | Cadott, Boyd, Thorp | Stanley Wwtp | May 7 | Oct 3 | 147 |
| Stevens Point | Plover, Polonia, Junction | Stevens Pt | May 4 | Oct 7 | 155 |
| Superior | — | Pattison Ranger Staion | May 18 | Oct 3 | 135 |
| Tomah | Babcock, Pittsville, Warrens, Millston | Mather 3 Nw | May 6 | Oct 3 | 148 |
| Tomahawk | Merrill | Merrill | May 11 | Sep 30 | 139 |
| Union Center | Yuba | Hillsboro | May 5 | Oct 4 | 153 |
| Washburn | Mason | Ashland Kennedy Mem Ap | May 23 | Sep 29 | 125 |
* Independence is this group's median-season location — the calendar below is computed from its data.
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Planting calendar (Independence, representative)
Computed from Independence's average frost dates — the median-season location in this Wisconsinzone 4b group. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees — your own location's dates may run a week or two earlier or later (see the table above).
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting | Season fit |
|---|---|---|---|---|---|---|
| Tomato | Tender | Mar 15 – Mar 29 | May 17 – May 24 | Jul 16 – Aug 5 | — | matures comfortably |
| Pepper | Very tender | Mar 1 – Mar 15 | May 24 – May 31 | Jul 23 – Aug 22 | — | matures comfortably |
| Cucumber | Tender | Apr 12 – Apr 19 | May 17 – May 24 | Jul 6 – Jul 26 | — | matures comfortably |
| Summer squash / zucchini | Tender | — | May 17 – May 24 | Jul 1 – Jul 16 | — | matures comfortably |
| Bush bean | Tender | — | May 17 – May 24 | Jul 6 – Jul 16 | Aug 3 – Aug 13 | matures comfortably |
| Sweet corn | Tender | — | May 10 – May 24 | Jul 9 – Aug 8 | — | matures comfortably |
| Basil | Very tender | Mar 29 – Apr 12 | May 17 – May 24 | Jun 16 – Jul 1 | — | matures comfortably |
| Lettuce | Half-hardy | Mar 29 – Apr 12 | Apr 12 – Apr 26 | May 27 – Jun 11 | Jul 20 – Aug 4 | matures comfortably |
| Pea | Hardy | — | Mar 29 – Apr 12 | May 23 – Jun 7 | Jul 10 – Jul 25 | matures comfortably |
| Spinach | Hardy | — | Mar 29 – Apr 12 | May 8 – May 18 | Jul 30 – Aug 9 | matures comfortably |
| Carrot | Half-hardy | — | Apr 19 – Apr 26 | Jun 18 – Jul 8 | Jun 30 – Jul 20 | matures comfortably |
| Broccoli | Half-hardy | Mar 15 – Mar 29 | Apr 12 – Apr 26 | Jun 6 – Jun 26 | Jul 5 – Jul 25 | matures comfortably |
Which crops fit this growing season
Using Independence's own 144-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.
Frost & freeze dates (Independence)
From NOAA's 1991–2020 Climate Normals at station USC00475563. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | May 20 | Jun 2 | Sep 23 | Oct 5 | 125 |
| 32°F (freeze) | May 10 | May 25 | Oct 2 | Oct 13 | 144 |
| 28°F | Apr 30 | May 14 | Oct 9 | Oct 24 | 163 |
| 24°F | Apr 18 | May 4 | Oct 21 | Nov 5 | 185 |
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. This group's median GDD (base 50°F) across all 63 locations is 2,241; Independence's own reading is shown below.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 2,793 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 4,794 | cool-season crops (brassicas, greens) |
Hardiness zone 4b in Wisconsin
Zone 4b means an average annual extreme minimum winter temperature of about −25 to −20 °F on the USDA's 2023 map — the number that tells you which perennials, shrubs, and trees reliably survive an average winter here. It does not set your planting dates, which come from the frost calendar above. Wisconsin spans 5 hardiness zones in this dataset — see all Wisconsin locations for the full range, including zones4a, 5a, 5b, 6a.
Explore zone 4b in other states at zone 4b, or see all USDA hardiness zones.
Frequently asked questions
- What does USDA hardiness zone 4b mean in Wisconsin?
- Zone 4b means an average annual extreme minimum winter temperature of −25 to −20 °F — the standard USDA measure of which perennials survive winter. 63 locations in Wisconsin fall in this zone. It does not set planting dates; see the frost calendar below for that.
- Where in Wisconsin's zone 4b is the growing season longest?
- Fountain runs the longest season on this page at about 180 days; Long Lake is shortest at about 95 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
- When should I plant tomatoes in Wisconsin's zone 4b?
- Using Independence's frost dates (this page's median-season location): start seeds indoors about Mar 15 – Mar 29, then transplant outside about May 17 – May 24. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
- Does every location in Wisconsin's zone 4b have the same frost dates?
- No — they do not all share a weather station, so frost dates vary by a week or more across the 63 locations listed (see the table above for each location's own dates).
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.