Wisconsin Planting Zones by City and ZIP Code
Wisconsin runs from zones 3b to 6a; 30% of its ZIPs are 5b, Milwaukee is 6a and Madison is 5b.
Wisconsin runs from zones 3b to 6a
The coldest night of the winter averages -35°F to -30°F in the coldest of Wisconsin’s ZIP codes and -10°F to -5°F in the warmest. Most of the state is zone 5b.
Planting zones of Wisconsin cities
| City | Zone | Coldest night, on average | Since 2012 |
|---|---|---|---|
| Milwaukee53202 | 6a | -10°F to -5°F | half a zone warmer than 2012 (5b) |
| Madison53703 | 5b | -15°F to -10°F | half a zone warmer than 2012 (5a) |
| Green Bay54301 | 5b | -15°F to -10°F | half a zone warmer than 2012 (5a) |
| Eau Claire54701 | 4b | -25°F to -20°F | same as 2012 |
| La Crosse54601 | 5a | -20°F to -15°F | half a zone warmer than 2012 (4b) |
| Superior54880 | 4b | -25°F to -20°F | same as 2012 |
Tap a ZIP for that address’s frost dates and this month’s jobs.
Find your zone anywhere in Wisconsin
A ZIP code or a town gives you its zone, how it moved since 2012, the frost dates at the nearest NOAA station, and the jobs for this month timed from them.
What to plant in Wisconsin this month
The calendar for each of Wisconsin's main zones, from vegetables to pruning and winter protection, each job tied to the extension page it comes from. Pick a month, or read the whole year below it.
Timed from the median frost dates of the 53 NOAA stations in Wisconsin’s zone 5b: last spring frost May 1, first fall frost Oct 12. Your own ZIP’s frost dates move every window, so the ZIP tool times them for you.
Pick a month above to see every job in it.
The year at a glance
- Start vegetable seeds indoorsJan to Apr
- Sow vegetables in the gardenApr to May
- Sow the fall vegetable gardenJun to Aug
- Set out transplantsApr to May
- Plant trees and shrubsMar 20 to May 15 and Sep 28 to Nov 16
- Plant garlicSep 28 to Nov 2
- Plant tulips and other spring bulbsOct 19 to Oct 26
- Divide fall-blooming perennialsApr 10 to May 22
- Divide spring and summer-blooming perennialsAug 31 to Oct 12
- Prune trees and summer-flowering shrubs while dormantFeb 20 to Apr 3
- Prune spring-flowering shrubs after they bloomApr 17 to Jun 12
- Water evergreens and new plantings until the ground freezesSep 14 to Nov 23
- Mulch perennial crowns once the ground freezesNov 23 to Dec 7
- Pull back the winter mulchMar 13 to Mar 27
- Put hardware cloth around young tree trunksOct 12 to Nov 23
- Dig and store canna, dahlia and gladiolusOct 12 to Oct 19
- Cut back perennials after a hard freezeOct 19 to Nov 16
What changed in Wisconsin since 2012
Every ZIP on both mapsCompared ZIP by ZIP from the 2023 and 2012 USDA tables; 872 Wisconsin ZIP codes appear in both.
Why Wisconsin’s zones moved
Of the cities above, Milwaukee went from 5b to 6a, Madison went from 5a to 5b, Green Bay went from 5a to 5b and La Crosse went from 4b to 5a.
The USDA explains the national picture: “When compared to the 2012 map, the 2023 version reveals that about half of the country shifted to the next warmer half zone, and the other half of the country remained in the same half zone.” The new map uses 1991 to 2020 and more than 13,000 weather stations, so it draws Wisconsin’s hills, valleys and cities more finely than the 2012 map did.
A warmer zone changes which perennials and shrubs come through the winter, not when the garden gets planted; that still follows the frost dates.
Frost dates and seed starting in Wisconsin
Wisconsin planting zone questions
Planting zones by state
Sources. USDA Plant Hardiness Zone Map, ZIP code tables (2023 and 2012), PRISM Climate Group, Oregon State University; USDA Plant Hardiness Zone Map; USDA Unveils Updated Plant Hardiness Zone Map (USDA Agricultural Research Service, November 15, 2023); NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal, by station (v1.0.1); NC State Extension Gardener Plant Toolbox. Zones are read from the PRISM ZIP code tables, read Oct 9, 2026; a ZIP code’s zone is the zone at its center. The calendar’s extension sources are listed on the planting zones page and under each job.