Wisconsin Planting Guide: What to Grow and When
Wisconsin gardeners deal with some of the most variable growing conditions in the Midwest — a short, intense spring that can flip from frost to heat in two weeks, summers that are warm but rarely brutal, and falls that arrive suddenly in the north. Whether you’re working a suburban plot near Milwaukee or a backyard garden in the Northwoods, knowing your specific zone and timing your plantings around Wisconsin’s frost windows is what separates a productive season from a frustrating one.
This Wisconsin planting guide covers everything you need: USDA hardiness zones across the state, frost dates by region, a month-by-month calendar, and the vegetables, flowers, and fruits that genuinely thrive here. The guide is organized around Wisconsin’s three distinct growing regions because what works near Chicago’s latitude (zone 5b south) simply does not apply to Superior on the Lake Superior shore (zone 4a).
Wisconsin’s growing season is shorter than most gardeners wish, but the cool springs and mild summers are ideal for cold-tolerant crops that struggle in hotter states. Brassicas, root vegetables, and spring greens can be exceptional here. Tomatoes and peppers need more planning but absolutely work with the right variety selection and timing. If your zone rating has shifted in recent years, that’s consistent with patterns across the upper Midwest — our overview of climate zone migration explains what’s changing and what it means for Wisconsin gardeners.
Wisconsin’s USDA Hardiness Zones
Wisconsin spans five hardiness zones, from zone 3a in the extreme north near the Michigan border down to zone 5b along the Illinois state line. Most of the state falls in zones 4 and 5, which means reliable cold winters, moderate summers, and a spring planting season that runs from late April through late May depending on location.
Zone 3a covers a narrow band in Iron and Vilas counties where winter lows can reach –40°F. Zone 3b extends through much of Ashland, Bayfield, and Douglas counties. Zone 4a covers a broad swath of central and northwestern Wisconsin including Wausau, Rhinelander, and Superior. Zone 4b includes Green Bay, Appleton, and the Fox Valley. Zone 5a covers Madison and most of south-central Wisconsin, while zone 5b covers Milwaukee, Racine, Kenosha, and the Lake Michigan shoreline.
Microclimates matter more in Wisconsin than in many states. The Lake Michigan shoreline moderates temperatures significantly — Milwaukee and communities along the eastern shore often get a 2–3 week longer season than inland locations at the same latitude. Urban heat islands in Milwaukee, Madison, and the Fox Cities push effective zone ratings up by half a zone in many gardens.
Wisconsin Frost Dates by Region
Knowing your last spring frost and first fall frost dates is the single most important piece of information for planning a Wisconsin garden. These dates vary by three to four weeks between the southern tier and the Northwoods. The table below shows 50% probability dates — for sensitive transplants, protect plants until you’re past the 10% date, which falls roughly two weeks later in spring.
| Location | Zone | Avg Last Frost | Avg First Frost | Growing Season |
|---|---|---|---|---|
| Milwaukee | 5b | April 20 | October 28 | ∼190 days |
| Racine / Kenosha | 5b | April 25 | October 25 | ∼183 days |
| Madison | 5a | May 5 | October 15 | ∼163 days |
| La Crosse | 5a | April 28 | October 12 | ∼167 days |
| Green Bay | 4b | May 10 | October 8 | ∼151 days |
| Appleton / Fox Valley | 4b | May 8 | October 10 | ∼155 days |
| Eau Claire | 4b | May 10 | October 5 | ∼148 days |
| Wausau | 4a | May 15 | September 28 | ∼136 days |
| Rhinelander | 4a | May 20 | September 22 | ∼125 days |
| Superior | 4a | May 22 | September 20 | ∼121 days |
| Ashland | 4a | May 25 | September 18 | ∼116 days |
| Hurley | 3b | June 1 | September 10 | ∼101 days |
The Three Wisconsin Growing Regions
Southern Wisconsin (Zones 5a–5b)
The southern tier — roughly the area south of a line running from La Crosse through Madison to Sheboygan — has the longest growing season in the state. Milwaukee and Racine are reliably zone 5b, and some protected spots near the lake in Milwaukee County can push zone 6 performance in a warm year. Last frost here typically falls in late April to early May, with first fall frost arriving in mid-to-late October. That’s a 165 to 190 day season, long enough for most vegetables including full-season tomatoes, peppers, melons, and sweet corn.
Madison is solidly zone 5a with a slightly shorter season than Milwaukee but strong agricultural extension resources through UW-Madison. The Driftless Area — the rugged, unglaciated terrain around La Crosse and southwest Wisconsin — creates considerable microclimate variation, with sheltered river valleys often running warmer than the surrounding landscape.
Southern Wisconsin gardeners can grow the full range of vegetables and a wide selection of marginally-hardy perennials. Gardeners near Milwaukee have successfully overwintered zone 6 plants like figs with winter protection.
Central Wisconsin (Zones 4b–5a)
Central Wisconsin — Green Bay, Appleton, Oshkosh, Sheboygan, Eau Claire, and the Fox Valley — sits in zones 4b to 5a with a season of roughly 148 to 160 days. That’s adequate for most vegetables but requires more careful variety selection for heat-loving crops.
Tomatoes work well in this region with varieties like Celebrity, Early Girl, and Jet Star. The key is choosing 65–75 day varieties rather than 85-day indeterminate types that may not fully ripen before September frosts, and getting transplants in promptly after the last frost (typically May 8–15). Pairing slow-maturing crops with fast-maturing companions is one strategy that pays off here — our companion planting guide covers combinations particularly useful in shorter-season gardens.
Green Bay sits on a bay that moderates temperatures compared to inland areas at the same latitude. The Fox Valley cluster of cities generally tracks with Green Bay timing but can run a few days earlier due to urban heat effects.
Northern Wisconsin (Zones 3b–4b)
Northern Wisconsin — Wausau north through Rhinelander, Ashland, Superior, and the Northwoods — is the most challenging gardening region in the state. Seasons run 90 to 136 days, and frosts can occur in late May or early June and return as early as mid-September.
This does not mean gardening is hopeless — it means gardening is different. Cold-hardy vegetables like kale, spinach, beets, carrots, cabbage, and peas can be outstanding in northern Wisconsin. The cool summers that frustrate tomato growers actually favor cool-season crops, which can be harvested well into October. Tomatoes are possible in the north but require very early varieties (60–65 days from transplant), starting seeds 8–10 weeks indoors, and using season-extension tools.
Wisconsin Month-by-Month Planting Calendar
The calendar below uses Madison (zone 5a) as the central baseline. Adjust earlier by 1–2 weeks for Milwaukee and the southeast, and later by 2–4 weeks for Green Bay, Wausau, and northern Wisconsin.
| Month | Task | Notes |
|---|---|---|
| Mid-February | Start peppers and eggplant indoors | 10–12 weeks before last frost; use heat mat, 80–90°F for germination |
| Late February | Start onions from seed indoors | 10–12 weeks before transplanting; or use sets instead |
| Early March | Start celery and celeriac indoors | 10–12 weeks; slow to germinate, keep moist |
| Mid-March | Start tomatoes indoors (south WI) / Start tomatoes north WI | 6–8 weeks before last frost; don’t start too early — leggy transplants underperform |
| Late March | Start broccoli, cabbage, cauliflower indoors (south WI) | 4–6 weeks before transplanting outdoors |
| Early April | Direct sow peas, spinach, lettuce outdoors (south WI) | Soil workable; 4 weeks before last frost; these handle light frost |
| Mid-April | Transplant broccoli, cabbage seedlings outdoors (south WI); start brassicas indoors (north WI) | Harden off transplants first; cover if hard frost expected |
| Late April | Direct sow beets, carrots, radishes, turnips outdoors (south WI) | Cool soil is fine for root crops |
| Early May | Direct sow peas, spinach outdoors (central WI); transplant broccoli (central WI) | ∼2 weeks behind Madison timing |
| Mid-May | Transplant tomatoes, peppers (south WI after last frost) | Wait for soil temp 60°F; use walls of water for extra protection |
| Late May | Transplant tomatoes, squash, cucumbers (south WI); last frost risk passed | Direct sow beans, squash, cucumbers; transplant warm-season crops (central WI) |
| Early June | Plant basil outdoors; direct sow beans, summer squash (central WI); transplant tomatoes (north WI) | Basil needs warm nights (50°F+); in north, use row cover on tomatoes first 2 weeks |
| Late June / July | Succession sow beans and lettuce; start brassica transplants for fall (late July) | Succession planting every 2–3 weeks extends harvest; start fall broccoli, cabbage 10 weeks before first fall frost |
| August | Direct sow spinach, kale, arugula for fall (south and central WI) | 6–8 weeks before first frost; kale sweetens after frost; plant garlic mid-to-late September |
| September | Plant garlic for overwintering; harvest continues; apply mulch to perennials after hard freeze | Garlic planted 4–6 weeks before ground freezes; hard freeze in north mid-September |
| October | Harvest root crops, kale, Brussels sprouts; protect tender perennials | Kale improves with light frost; Brussels sprouts best after frost; mulch perennial crowns once frozen |
Best Vegetables for Wisconsin Gardens
Wisconsin’s climate is well-suited to cold-tolerant vegetables, and with careful variety selection it supports the full range of warm-season crops throughout most of the state. The crops below are ranked by overall reliability across Wisconsin’s zones.
| Vegetable | Best Zones | Days to Harvest | Wisconsin Notes |
|---|---|---|---|
| Kale | 3–5b | 50–65 days | Grows all season; sweetens after frost; one of WI’s best crops across all zones |
| Bush beans | 4–5b | 50–60 days | Direct sow after last frost; 2–3 succession plantings possible in southern WI |
| Broccoli | 3–5b | 60–80 days (transplant) | Spring and fall crops; cool weather improves flavor and head size |
| Zucchini | 4–5b | 47–55 days | Prolific in all zones; one to two plants per household is typically enough |
| Peas | 3–5b | 55–70 days | Direct sow as early as possible; finished before summer heat; excellent in north WI |
| Tomatoes | 4–5b | 60–80 days | Full-season types for southern WI; 60–65 day varieties for north with season extension |
| Spinach | 3–5b | 40–50 days | Spring and fall crops; plant as early as soil is workable; fall crop often better |
| Beets | 3–5b | 50–70 days | Direct sow; fall beets are among the best crops for WI — cold improves sweetness |
| Carrots | 3–5b | 65–80 days | Direct sow in deep, loose soil; fall harvest carrots left in ground taste better after frost |
| Cabbage | 3–5b | 70–90 days (transplant) | Very reliable across WI; spring and fall crops; storage types keep through winter |
| Cucumbers | 4–5b | 55–65 days | Need heat and warm soil; best in southern and central WI; use black plastic mulch |
| Sweet corn | 4b–5b | 65–90 days | Needs warm summers; southern WI reliable; marginal in north without very early varieties |
| Winter squash | 4–5b | 80–110 days | Choose 90-day varieties for northern zones; delicata and acorn are more reliable than butternut in short seasons |
| Peppers | 5a–5b | 70–90 days | Reliable in southern WI; marginal in central and north; need warm soil and warm nights to set fruit |
For best results with tomatoes in zones 4a and 4b, look for varieties bred specifically for short seasons: Siletz (52 days), Stupice (62 days), Fourth of July (49 days), and Glacier (55 days) consistently outperform standard mid-season types in northern and central Wisconsin. In southern Wisconsin, Celebrity, Early Girl, Better Boy, and most mid-season varieties do well.
Flowers and Perennials for Wisconsin
Wisconsin’s cold winters actually favor many perennials that struggle in warmer climates, and the state’s native plant palette is genuinely excellent.
Native Wisconsin Perennials
Purple coneflower (Echinacea purpurea) is one of the easiest and most rewarding perennials for Wisconsin gardens. Hardy to zone 3, it blooms from midsummer through early fall, requires almost no maintenance once established, and attracts pollinators throughout the season. Goldfinches eat the seed heads in winter — leave them standing for late-season wildlife value.
Black-eyed Susan (Rudbeckia fulgida and hirta) is another native that thrives across all Wisconsin zones. It blooms from July through October and seeds freely to naturalize over time. Rudbeckia fulgida ‘Goldsturm’ is the most widely planted cultivar; Rudbeckia hirta volunteers more freely from seed in naturalistic plantings.
Baptisia (wild indigo, Baptisia australis) is slow to establish — it takes 2–3 years to settle in — but then persists for decades with no care. It gets large (up to 4 feet wide), produces blue-purple flowers in late spring followed by attractive inflated seed pods, and is hardy to zone 3. Do not move it once established; the taproot does not recover from transplanting.
Wild bergamot (Monarda fistulosa) and bee balm (Monarda didyma) are native to Wisconsin and excellent for pollinators, hummingbirds, and butterflies. Both spread by rhizome; site them where they can roam or divide annually to keep them in bounds.
Reliable Garden Perennials
Hostas are among the most dependable perennials for Wisconsin, particularly in shade or partial shade. Hardy to zone 3, they return reliably year after year and expand into substantial clumps without much attention. The main threat in Wisconsin is slug pressure in wet years, which hosta growers manage with diatomaceous earth or iron phosphate bait.
Stop missing your zone's planting windows.
Select your US zone and month — get a complete checklist of what to plant, prune, feed, and protect right now.
→ View My Garden CalendarDaylilies are another bulletproof choice across all Wisconsin zones. Most are hardy to zone 3–4 and bloom prolifically with minimal care. Because most daylilies bloom for only 3–4 weeks, plant 3–4 varieties with staggered bloom times — early (June), midseason (July), and late (August) — for a longer season of color.
Garden phlox (Phlox paniculata) blooms in mid-to-late summer when many other perennials are past peak. Choose mildew-resistant cultivars — ‘David’ (white), ‘Robert Poore’ (pink-purple), and ‘Speed Limit 45’ (lavender) have the best resistance records in the Midwest.
Sedum (now reclassified as Hylotelephium for the upright types) is excellent for Wisconsin’s sometimes-dry summers. ‘Autumn Joy’ and ‘Matrona’ are both zone 3 hardy and provide late-season color from August through October. They require no staking, tolerate drought, and attract late-season pollinators.
Astilbe is ideal for moist, partly-shaded sites in Wisconsin. Hardy to zone 3, it blooms in feathery plumes of white, pink, red, or purple in early to midsummer and provides attractive texture the rest of the season.
Fruit Growing in Wisconsin
Wisconsin is excellent territory for cold-hardy fruit, with a long tradition of apple and berry production across the state.
Apples are among the most reliable fruit crops in Wisconsin. Hardy varieties like Honeycrisp, Haralson, Regent, and Zestar! handle zone 4 winters without problems. The UW-Madison apple breeding program and the University of Minnesota program have both developed varieties specifically for upper-Midwest conditions. In southern Wisconsin, a wider range of varieties succeeds, including many standard commercial types. Apples are a multi-decade commitment — choose your site carefully, in full sun with good drainage and air circulation to reduce disease pressure.
Strawberries are among the most accessible fruit crops for Wisconsin home gardeners. June-bearing types (Jewel, Honeoye, Sparkle) produce heavily in June and July; day-neutral types (Albion, Seascape, Albion) produce smaller quantities but over a much longer season from June through September. Strawberries are cold-hardy through zone 3 with winter mulching.
Raspberries and blackberries work well in zones 4b through 5b. Hardy red raspberry varieties — Boyne, Nova, Killarney — are reliable to zone 3. Fall-bearing varieties like Heritage and Caroline often perform especially well in Wisconsin because they ripen their heaviest crop in the cooler, moister August–September conditions. Wild blackberries (Rubus allegheniensis) grow naturally across much of Wisconsin; cultivated varieties like Chester and Triple Crown do well in southern and central zones.
Blueberries are possible in Wisconsin but require careful soil management. Most Wisconsin soils are too alkaline for blueberries, which need pH 4.5–5.5. Raised beds filled with acidified growing medium (peat moss, pine bark, sulfur) are the practical approach for most Wisconsin gardeners. Hardy varieties including Northblue, Northsky, and Polaris were developed specifically for zone 4 conditions.
Currants and gooseberries are underused but excellent for northern Wisconsin. Both handle zone 3 with no difficulty, produce reliably with little care, and are excellent for jam, juice, and fresh eating. Unlike many fruit crops, they tolerate partial shade and do not need the best-drained soils in your garden.
Wisconsin Gardening Tips for a Short Season
Season extension is essential for most Wisconsin gardeners, particularly in central and northern regions. These techniques can effectively add weeks on both ends of the growing season.
Start seeds at the right time indoors. Peppers and eggplant need 10–12 weeks before transplant date; use a heat mat because they need soil temperatures of 80–90°F to germinate well. Tomatoes need 6–8 weeks. The common mistake is starting too early — leggy, root-bound 10-week-old tomatoes do not outperform properly-timed 6-week-old ones. Count backward from your local last frost date, not from a calendar recommendation written for a generic audience.
Warm your soil before planting. Black plastic mulch can raise soil temperature by 5–10°F at planting depth, which makes a real difference for tomatoes and peppers in zones 4a and 4b. Lay it a week or two before transplanting. It also suppresses weeds through the peak of summer. IRT (infrared transmitting) mulch warms soil even faster than black plastic and is worth the extra cost in short-season gardens.
Use row covers aggressively. Floating row cover (Agribon-19 or -30) can protect transplants from late frosts, extend the fall season by several weeks, and shield cool-season crops from early insect pressure in spring. In northern Wisconsin, consistent use of row covers and low tunnels can effectively add 3–4 weeks to both ends of the season.
Select varieties for your actual zone. This matters more than any other decision. A standard indeterminate tomato that takes 80+ days may produce well in Milwaukee but will leave you waiting in Rhinelander while the first frost arrives. Seed companies focused on short-season production — Fedco Seeds (Maine), High Mowing Organic Seeds (Vermont), and Johnny’s Selected Seeds (Maine) — carry varieties bred specifically for upper-Midwest conditions. Many of their best offerings came from breeding programs specifically designed for the short, cool seasons of the northern US.
Plant warm-season crops into warm soil, not just a warm calendar. Tomatoes transplanted into soil below 60°F stall out, sometimes for weeks, and often develop problems. A soil thermometer is one of the most useful tools a Wisconsin gardener can own. Wait until soil temperature at 4 inches reads at least 60°F before putting in tomatoes, peppers, cucumbers, or squash, even if the air temperature looks fine.
Plan a fall garden in July. Wisconsin’s cool falls are genuinely excellent for kale, spinach, arugula, turnips, and radishes. Many Wisconsin gardeners get their best kale in October. The timing trick is counting backward from your first fall frost: kale and broccoli transplants need to go in 8–10 weeks before that date, meaning late July for central and northern Wisconsin. For more on making the most of shoulder-season windows, see our guide to year-round planting.
Frequently Asked Questions
What grows best in Wisconsin?
Cold-tolerant vegetables are the stars of Wisconsin gardens: kale, broccoli, peas, spinach, beets, carrots, and cabbage are reliable across all zones. Native perennials including coneflower, black-eyed Susan, and baptisia thrive statewide. For fruit, apples and raspberries are the most reliable long-term choices.
When should I start seeds indoors in Wisconsin?
Pepper and eggplant seeds should be started 10–12 weeks before your last frost date. Tomatoes need 6–8 weeks. For Madison (last frost around May 5), that means tomatoes in mid-March and peppers in mid-February. Adjust earlier by 1–2 weeks for Milwaukee, and later by 2–3 weeks for Green Bay and Wausau, or 3–4 weeks for Rhinelander and Superior.
What USDA zone is Wisconsin?
Wisconsin spans zones 3a (far north, winter lows to –40°F) through 5b (southeast corner along Lake Michigan). Most of the state falls in zones 4a, 4b, or 5a. Your county’s specific zone is shown on the USDA Plant Hardiness Zone Map at planthardiness.ars.usda.gov.
When is the last frost in Wisconsin?
Last frost dates range from around April 20 in Milwaukee (zone 5b) to June 1 or later in the far north (zone 3b). The middle of the state — Green Bay, Wausau — typically sees last frost between May 8 and May 20. Always use your local 10-year average for precision planting decisions rather than statewide generalizations.
What vegetables grow well in northern Wisconsin?
Northern Wisconsin gardeners do best with cold-tolerant crops: kale, spinach, beets, carrots, peas, broccoli, cabbage, turnips, and kohlrabi. Short-season tomato varieties (60–65 days from transplant) like Siletz, Stupice, and Fourth of July can succeed with season-extension techniques. Focus on crops that love the climate rather than fighting it with heat-lovers that barely make it.
Can I grow tomatoes in Wisconsin?
Yes — tomatoes grow reliably throughout southern and central Wisconsin (zones 4b–5b) with standard mid-season varieties. In northern Wisconsin (zones 3b–4a), use very early varieties (60–65 days) and season-extension tools including row covers and black plastic mulch. The key rule is timing: transplant after soil temperature reaches 60°F, usually late May to early June depending on zone.
Does Wisconsin have a good growing season for gardening?
Wisconsin’s growing season is short by national standards but well-suited to a specific range of crops. The cool springs and mild summers are ideal for brassicas, root vegetables, peas, and leafy greens. Summer heat is usually moderate enough that cool-season crops can be grown in spring and fall, sometimes with a brief summer break. The main constraint is the short window for heat-loving crops in zones 3b–4a.
