Fruit Trees for Oshkosh, Ripon and Lake Winnebago, Wisconsin

On January 30, 1951, NOAA's station at the Fond du Lac wastewater plant, at lake level on the south end of Lake Winnebago, read −41°F, the coldest reading on record anywhere on this map. Oshkosh read −32°F that morning. Growing fruit trees for Oshkosh, Ripon and Lake Winnebago comes down to knowing which kind of ground you're on. The map covers the west side of the lake and the country behind it in east-central Wisconsin's Winnebago, Fond du Lac and Green Lake counties: Oshkosh, the north part of Fond du Lac, Taycheedah, Van Dyne, Omro, Winneconne, Butte des Morts, Berlin, Ripon, Rosendale and Green Lake.

Type your address in the box on the map to get the number for your own place, and the list of what we sell that has come through it.

How to read this map

The big number is the 30-year planning low our cold hardiness calculator uses, built from NOAA station records since the 1995-96 winter, nudged for the ground around you. It's a safe number to plan around, not the record and not a promise of how often it comes. The MFTC zone is that number in half zones. The typical winter is an average year's coldest night, the kind of average USDA's map is built on. The spring layer shows how much warmer or colder a spot runs than downtown Oshkosh on a still, clear night at bloom.

Downtown Oshkosh plans for −23°F, MFTC zone 4b, typical winter −11°F, one of the warmest spots on the map. The middle of the map is −27°F (4a), and nine tenths of the growing ground falls between −30°F and −24°F. The warm end is built-up Oshkosh, Nekimi and Berlin (−23°F to −24°F) and the slopes above Taycheedah (a median −24°F). The cold end is Green Lake, where the low ground runs a median −31°F and Blackbird Point plans for −33°F, MFTC 3b. The spring layer swings wider: from 6°F colder than Oshkosh at Arcade Acres, on low ground west of Ripon, to 9°F warmer on Tuleta Hills above Green Lake.

Why the map looks the way it does

Lake Winnebago fills a basin worn into soft Ordovician rock and rimmed by the harder Silurian rock of the Niagara Escarpment, which folks around Fond du Lac call the Ledge. The west side, this map, is a broad, nearly flat lake plain: Omro, Winneconne and the lakeshore settlements sit within about 20 feet of the lake's 746-foot surface. The Upper Fox comes in through Berlin and Omro, the Wolf through Lake Poygan and Winneconne, and both pass through Lake Butte des Morts into Winnebago at Oshkosh. Behind the lake the ground climbs to Ripon (932 feet) and the Rosendale upland (899 to 922 feet). On a clear, calm night chilled air slides off that upland along the Fox and the creeks, and on a plain this flat it has nowhere to go.

The lake is about 30 miles long but averages only 15.5 feet deep, too shallow to store much heat. It freezes hard enough for up to 10,000 cars to park on it and doesn't break up until March, so in midwinter the shore points plan for −25°F to −27°F, no warmer than the ground behind them. The lake earns its keep in fall. The old Oshkosh city station, near lake level, gets its first 32°F on a median October 20; Wittman Regional Airport, on the south side at 785 feet, October 11. That's 175 frost-free days against 159, and the Fond du Lac plant beats its airport 165 to 158. We haven't found a published reason, but it fits open, still-warm water in October plus some town heat.

On the worst nights the lake-level stations aren't the warm ones. The Fond du Lac plant sits on the flat ground south and west of the Ledge where, as the Wisconsin Ledge wine region's description puts it, cold air pools; on January 9, 1977 it read −32°F while Oshkosh read −25°F. The Oshkosh city station read −30°F on February 3, 1996. Wittman's record doesn't include that night, part of why the airport's 30-year number (−24°F) is milder than the city station's (−26°F).

Going west, the winter number gets colder, and the records back it up. The old El Dorado station (889 feet, 1940 to 1978), on the upland west of Fond du Lac, read −32°F on January 15, 1972, against −28°F at Oshkosh and −26°F at Fond du Lac. Just off the map, Dalton read −34°F on February 3, 1996, and on January 31, 2019 the Markesan plant, also just off the map, read −32°F, the coldest station in the group. So the map runs from −23°F in Oshkosh to −28°F at Ripon and −29°F at Green Lake, colder as you go west and away from the towns' heat.

The spring layer takes the terrain at full strength, and that's where height above the nearest low ground shows. Ripon sits on a hillside 90 feet above its floor, on a 9 percent slope, and reads 7°F warmer than Oshkosh on a still bloom night. Arcade Acres, 1.9 miles west-northwest in low ground, reads 6°F colder. Both plan for −28°F, because deep winter nights fill the whole country and our 30-year number takes the fine terrain at a quarter strength, but at bloom they're 14°F apart. Fisk sits 66 feet higher than downtown Oshkosh but only 10 feet above its own flat floor, and reads 6°F colder. Height alone doesn't buy warmth.

Towns hold heat too: downtown Oshkosh, North Park and Ferry Crossing plan for −23°F while the city's low lakeside edges plan for −26°F to −27°F. And this is red clay country. The Oshkosh soil, formed in red lake clay, runs 60 to 85 percent clay in the subsoil, and water moves through it slowly, and the Winneconne soil holds a perched water table 1.5 to 3.5 feet down for at least a month most years. Low, wet, grassy ground runs cold on a frost night, and UW Extension calls ground where water stands within 3 to 4 feet of the surface for weeks in spring probably unsuitable for apples.

Oshkosh: downtown, the lakefront and the neighborhoods

Downtown, on the Fox between Lake Butte des Morts and Lake Winnebago, is this map's reference point: −23°F, MFTC 4b, typical winter −11°F. Within 3 miles the floor runs a median −26°F, the warmest tenth of the ground −24°F and the coldest tenth −27°F. There's no bench ground; what moves the number is how built up a place is and how near the low lakeshore. North Park, 3.5 miles north and 30 feet above its floor, is the warmest named spot on the map at −23°F, and Ferry Crossing, toward Lake Butte des Morts, matches downtown; Lumber River beside it plans for −25°F. Toward the lake it steps colder: River East, Menominee South and Millers Bay −24°F (4b), Woodland Park −25°F, Northshore −26°F (4a), Stevens Park and Rockaway Beach −27°F, and Stony Beach, 2.3 miles south-southeast, −27°F with a typical winter of −16°F. Every one of these reads 1°F to 3°F colder than downtown at bloom.

Down by the water I'd plan a few degrees colder than the map: the city station carries its own 30-year number of −26°F and read −30°F in 1996. In the core and North Park, Liberty and Northern Spy apples, Stanley plum and Contender peach (all −30°F) have room, and Blushingstar peach (−25°F) wants a south wall. On the lakefront, lean on Honeycrisp and Wolf River (−45°F), Zestar!® and Cortland (−40°F), Ure pear (−40°F) and Superior plum (−35°F) with Toka (−45°F), which pollenizes it; our pollination maps show what pairs with what. North up the Fox, the Green Bay, Appleton and Fox Valley map takes over.

Fond du Lac, Taycheedah and the slopes toward the Ledge

Only the north part of Fond du Lac is on this map; the Fond du Lac, West Bend and Kettle Moraine map covers the rest. The map's Fond du Lac point plans for −25°F, MFTC 4a, typical winter −14°F, even with Oshkosh at bloom, with the floor nearby at −26°F and the coldest tenth at −28°F; North Fond du Lac, on the same flat ground, plans for −26°F. The wastewater plant's 122-year record is a warning, though: −41°F in 1951, −29°F in 1996, and a 30-year number of −27°F, and the county airport runs a median 3°F colder than the Oshkosh city station for the year's coldest night. By the lake and the river I'd plan for −28°F to −30°F and pick trees rated −35°F or colder, like Haralson apple (−45°F), Bartlett pear (−35°F) and Evan's Bali tart cherry (−45°F).

Taycheedah, 3.5 miles northeast at the lake's southeast corner, shows the biggest floor-to-slope contrast on the map. The village sits on the floor at 755 feet and plans for −27°F, MFTC 4a, typical winter −15°F; the floor within 3 miles runs a median −28°F, but the slopes above it toward the Ledge run −24°F. But a slope is only as good as its outlet: Peebles, 60 feet above its floor but in a draw, plans for −25°F and reads 2°F colder than Oshkosh at bloom, and Hunter's Grove, on the floor just south of Taycheedah, 4°F colder. The beach settlements from Luco to Welling Beach plan for −26°F to −27°F. On the open slopes, Sungold apricot (−40°F), Siberian C peach (−35°F) and Rainier cherry (−30°F) have the best shot at a crop.

Van Dyne, Nekimi and the west shore

The west shore is Lake Winnebago's shallow side, with reefs and islands, and its settlements sit at lake level: Black Wolf Point and Little Point plan for −27°F, Decorah Beach, Point Comfort and Paukotuk −26°F. Black Wolf Point, sloping 3 percent to the water, reads even with Oshkosh at bloom. Van Dyne, 40 feet above its floor but on flat ground, plans for −25°F, MFTC 4a, typical winter −14°F, and reads 2°F colder. Inland, Nekimi, 70 feet above its floor at 882 feet, plans for −24°F (4b), and Fitzgerald and Zion −25°F (4b), while flat Fisk reads 6°F colder than Oshkosh at bloom. Here Zestar!®, Cortland, Wolf River and Spartan (−45°F) apples, Ure pear and Superior with Toka are the safe picks.

Omro, Winneconne, Butte des Morts and the Upriver Lakes

Upstream, the Fox and the Wolf spread into the Upriver Lakes. Lake Butte des Morts, 7 feet deep on average and largely flooded marsh, flushes in about 6 days and only its shallow zone reliably freezes, but the map shows no warm shore: from Sunset Point and Oakwood to Harbor Springs and Rivermoor, the shore plans for −25°F to −27°F. What shows is slope. Butte des Morts, on the north shore 30 feet above its floor on a 5 percent slope, plans for −26°F, MFTC 4a, typical winter −15°F, yet reads 2°F warmer than Oshkosh at bloom; Harbor Springs, flat at the water, reads 4°F colder. Winneconne, on the Wolf River bottom in the middle of the Wolf chain of lakes, plans for −25°F, MFTC 4a, typical winter −14°F, 1°F colder at bloom.

Omro, 10 miles west of Oshkosh on the Fox, plans for −25°F, MFTC 4b, typical winter −14°F, and reads 3°F colder at bloom; the floor nearby runs −26°F. Island Park, 3.1 miles up the Fox, plans for −27°F and reads 5°F colder, the river bottom at its coldest. Roo's Apple Orchard, on County Road D between Omro and Winneconne, grows Wolf River, Cortland, Honeycrisp, Spartan, Wealthy, Sweet Sixteen, Snow Sweet and Whitney crab, plus plums and pears. All of those apples clear these bottoms by 13°F or more, and Luscious pear and Alderman plum (−40°F) fit too. Save apricots for the Butte des Morts slope.

Berlin and the upper Fox

Berlin, first called Strong's Landing, sits on the upper Fox where it runs north through town. The map's Berlin point, 20 feet above its floor at 779 feet, plans for −24°F, MFTC 4b, typical winter −13°F, and reads 2°F colder than Oshkosh at bloom; within 3 miles the floor runs −26°F. The wastewater plant, at 763 feet, shows the cold side: −27°F on January 31, 2019, and the shortest frost-free season of any station here, 152 days, with a median last 32°F of May 8 and one spring in ten May 17 or later. Koro, 5 miles east and 70 feet above its floor, plans for −26°F but reads 2°F warmer than Oshkosh at bloom. Berlin is apple, pear and bush fruit country: Honeycrisp, Northwest Greening and Golden Russet (−40°F), Ure pear, Alderman and Toka plums, Meteor tart cherry (−40°F) and honeyberries (−50°F). Save apricots and peaches for ground like Koro's.

Ripon, Rosendale and the western upland

The map's Ripon point, on a hillside at 948 feet, plans for −28°F, MFTC 4a, typical winter −16°F, yet reads 7°F warmer than Oshkosh at bloom. Within 3 miles the floor runs −28°F and the benches −27°F. Ripon Junction, half a mile northeast and 80 feet above its floor, plans for −27°F and reads 3°F warmer; Arcade Acres, in the low ground to the west-northwest, plans for −28°F and reads 6°F colder, the coldest bloom-night reading of any named spot on the map. So the two layers disagree here, and both matter. On Ripon's hill, Westcot and Morden 604 apricots (−45°F), Hardy Iowa apricot, Siberian C peach and Lapins cherry (−35°F) clear −28°F and have a fair shot at keeping their blossoms. Contender (−30°F) is worth a try against a south wall. In the hollows, stick to late-blooming apples, pears and bush fruit.

East-southeast of Ripon, Rosendale plans for −28°F, MFTC 4a, typical winter −15°F, and reads 1°F colder than Oshkosh at bloom; West Rosendale, Rosendale Center and Eldorado plan for −27°F to −28°F. Metomen, at 1,007 feet the highest named point on the map, plans for −28°F. Scattered rises do better: Woodhull, 70 feet above its floor, and Elo plan for −25°F, Pickett −27°F and 2°F warmer at bloom. With the El Dorado station's −33°F on record, I'd want trees rated −35°F or colder anywhere up here.

Green Lake: the bluffs, the bays and the cold shore

Green Lake is the deepest natural inland lake in Wisconsin, 237 feet at its deepest and 100 feet on average, in an old river-cut valley, probably deepened by ice, that a moraine dammed at the west end. Bluffs ring it: Lucas Bluff on the southeast shore, at 33 percent the steepest slope in the basin, Sugar Loaf on the north shore, Sandstone Bluff on the south. The city sits at Dartford Bay on the north side, where the Puchyan River drains the lake toward the Fox.

In winter this is the coldest corner of the map. The map's Green Lake point, at 805 feet, plans for −29°F, MFTC 4a, typical winter −15°F; the low ground within 3 miles runs a median −31°F against −27°F on the benches. Oakwood Point, at the water just south-southwest of town, plans for −30°F and reads 4°F colder than Oshkosh at bloom. Southwest down the lake, Lakewood Estates and Indian Hills plan for −31°F, Greenwyck −32°F and Blackbird Point −33°F. Heritage Village, on the west side of town, plans for −28°F, about the same as the town. Part of this is the cold upland. Part is the basin: cold air drains off the bluffs onto the water, and a pool fills to its lowest outlet, here the Puchyan, before it spills. Deep as it is, the lake still freezes over, a median 87 days a winter, and frozen water does nothing for the shore.

The bluffs flip that at bloom. Tuleta Hills, on a 21 percent slope 80 feet above its floor, plans for −30°F but reads 9°F warmer than Oshkosh, the best spring reading of any named spot on the map. Center House, on the upland 3.7 miles south of town and 140 feet above its floor, reads 7°F warmer, Lakewood Estates 5°F and Sandstone Bluff 4°F. On the bluffs, Westcot, Morden 604 and Debbie's Gold (−50°F) apricots and Siberian C peach (5°F to spare at −30°F) are the stone fruit I'd try. On the cold shore, go with Wealthy (−50°F), Frostbite (−45°F), Bolshaya pear (−50°F), Toka and Brookred (−50°F) plums, and Evan's Bali.

Spring frost and bloom around Lake Winnebago

The spring layer follows the same drainage as the winter cold: warmest on slopes with low ground below (Tuleta Hills, Ripon, Center House), coldest on flats and bottoms with nowhere to send the cold (Arcade Acres, Fisk, Island Park, Harbor Springs). Open blossoms of nearly every tree fruit start dying near 28°F, and Wisconsin's fruit specialists say that at full bloom 1°F can decide the crop.

NOAA's 1991 to 2020 records show the same order: the median last 32°F comes April 27 at the Oshkosh city station, May 2 at the Fond du Lac airport, May 4 at Wittman and May 8 at Berlin, and the last 28°F two to two and a half weeks earlier. One spring in ten the last 32°F comes May 13 or later at Oshkosh and May 20 or later at Wittman.

An April 2012 "killer frost" cut Wisconsin's fruit crop badly enough that USDA aid followed, and on May 14 and 15, 2016, frost hit apples and grapes across central and southern Wisconsin, with losses from none to 95 percent, while orchards near Lake Michigan reported little damage because that lake holds bloom back. Nobody has documented that kind of delay behind Lake Winnebago, which is iced in until March.

The fix is mostly site. Put apricots, peaches and sweet cherries on the slopes that read warmest: Ripon's hill, the Green Lake bluffs, the slopes above Taycheedah. Keep apples, pears, honeyberries and bush fruit on flatter ground; only about 15 percent of apple blossoms need to set for a crop, and fully open haskap (honeyberry) flowers take 19°F. Gap any hedge or tree line across the bottom of a slope; it backs cold air up into the trees above. Through bloom, mow short, don't till, and water a day or two before a frost; frost cloth of 0.5, 0.9 and 1.5 ounces per square yard gains about 4°F, 6°F and 8°F.

What the weather records say

The coldest NOAA station readings on file: −41°F at the Fond du Lac plant (January 30, 1951), with −39°F at Dalton that morning; −34°F at Oshkosh (February 20, 1929); −33°F at Menasha (February 21, 1936); −32°F at Markesan (January 31, 2019), when Wittman read −26°F.

Since 1995, six of the seven stations here have gone below their own 30-year number, all in February 1996 or January 2019: the Oshkosh city station hit −30°F against its −26°F, and the station southwest of Fond du Lac −27°F against −23°F. So I like a few degrees of room here. Timing matters too: the median first 32°F comes October 7 at Berlin and October 20 at Oshkosh, and a freeze before trees harden off kills at temperatures a January tree shrugs off, so we taper water from mid-August.

UW Extension notes the 2023 USDA map spread zone 5b to the ground around Lake Winnebago; that map is built on the average winter's coldest night, and Wittman and the Fond du Lac airport average −14°F and −15°F. Our MFTC zone is 4b in Oshkosh and 4a for most of the map, a full zone or more colder, because NOAA station records show the worst night in about 30 winters runs a median 13°F below a station's average winter low.

What you can grow here

Oshkosh's core, Nekimi, Berlin and the slopes above Taycheedah: −25°F or warmer

• Apples: Liberty, Northern Spy and Cox Orange Pippin (−30°F), plus everything hardier below.
• Pears, plums and cherries: D'Anjou pear, Stanley and Shiro plums, Rainier and Stella sweet cherries, Montmorency (all −30°F).
• Peaches and apricots: Contender and Veteran peaches, Harlayne apricot (−30°F); Blushingstar and Hardired nectarine (−25°F) only against a south wall.

The lake plain, the shores, the river towns and Ripon: −26°F to −28°F

• Apples: Empire and Freedom (−35°F); Zestar!®, Cortland and Golden Russet (−40°F); Honeycrisp, Wolf River, Snowsweet® and Spartan (−45°F).
• Pears: Bartlett and Seckel (−35°F); Ure, Luscious and Summercrisp (−40°F).
• Plums: Superior and Italian (−35°F) with Toka as pollenizer; Alderman (−40°F).
• Cherries: Lapins and Gold (−35°F), Meteor (−40°F), Evan's Bali (−45°F).
• Apricots and peaches, on slopes only: Hardy Iowa and Siberian C (−35°F), Sungold (−40°F), Westcot (−45°F). Worth a try: Contender (−30°F) on Ripon's hill or a south wall.
• Berries and vines: honeyberries and Montana Black Currant (−50°F), Pixwell gooseberry and Boyne raspberry (−40°F), Frontenac grape (−35°F).

Green Lake and its shore: −29°F to −33°F

• Apples: Wealthy (−50°F), Haralson and Frostbite (−45°F); Kerr (−50°F) and Trailman (−60°F) applecrabs, the ones to plant if you only plant one tree.
• Pears and plums: Bolshaya and Krasnobokaya pears (−50°F); Toka (−45°F), Brookred and Brookgold plums (−50°F).
• Cherries and apricots: Evan's Bali (−45°F), Nanking cherry (−50°F); Westcot, Morden 604 and Debbie's Gold apricots on the bluffs.
• Berries: honeyberries, Aronia and Montana Black Currant (−50°F).

Drainage comes first on this clay: test it before you plant (dig 2 feet, fill, let it drain, refill; under 10 hours is well drained) and use your best-drained ground. UW suggests B.9, M.9, G.11, G.41, M.26, G.935, G.30 or M.7 for home apples, noting M.9 and M.26 are very susceptible to fire blight. Roots are the weak link: dormant apple roots are seriously hurt near 10°F while the wood takes about −40°F, and after Wisconsin's snowless 2024-25 winter UW found damage just below the graft union. Hold snow over the roots and mulch. Apple scab is Wisconsin's most serious apple disease, worst in wet weather April through early June; watch too for cedar-apple rust, fire blight after warm, wet bloom weather, and cankers entering through southwest trunk injury (paint trunks white). Apples need a second variety blooming at the same time within about 200 yards.

Fruit history here

The local apple is the Wolf River, a chance seedling found on the shore of the Wolf River and known by 1875, the same river that runs through Winneconne onto this map. Its fruit often goes over a pound, it's prized for cooking and apple butter, UW lists it as resistant to scab and fire blight, and it's come through −45°F. Northwest Greening (Northwestern Greening) is another Wisconsin apple. Wisconsin's commercial cranberry industry began around Berlin.

Questions people ask

What growing zone is Oshkosh, Wisconsin?

Downtown Oshkosh plans for −23°F, MFTC zone 4b, with a typical winter of −11°F, and most of the map around it is 4a. UW Extension says the 2023 USDA map put the ground around Lake Winnebago in zone 5b. USDA's zone is based on an average winter, ours on the bad night we plan for.

When is the last frost in Oshkosh?

NOAA station records for 1991 to 2020 put the median last 32°F at April 27 at the city station near the lake and May 4 at Wittman airport. One spring in ten it comes May 13 or later in the city and May 20 or later at the airport.

Does Lake Winnebago keep Oshkosh warmer?

In fall, yes: the city station near the lake gets its first 32°F around October 20, nine days after the airport, and has 175 frost-free days to the airport's 159. In midwinter, no. The lake averages 15.5 feet deep and freezes hard, and the shore plans for −25°F to −27°F.

Can you grow peaches in Oshkosh?

Yes. Contender and Veteran (−30°F) clear downtown's −23°F with 7°F to spare, and Siberian C (−35°F) clears every named spot on the map. They bloom early, so plant them on ground that reads warm at bloom.

What fruit trees grow in the clay soil around Oshkosh?

Most of it is red, slow-draining lake clay, some with a perched water table 1.5 to 3.5 feet down. Test drainage and plant your best-drained ground. There, Honeycrisp, Wolf River, Zestar!®, Ure pear, Superior plum with Toka, and honeyberries all clear the lake plain's −26°F to −27°F.

Why is Green Lake colder than Oshkosh?

It sits on the cold western upland, and its basin pools cold air off the bluffs. It plans for −29°F and its low ground −31°F, against Oshkosh's −23°F. The bluffs make up for it at bloom: Tuleta Hills reads 9°F warmer than Oshkosh on a still spring night.

Warmer spots, colder spots

Here's the number to plan for at named places on the map, warmest first. Each one is the 1-in-30-year low for that spot: the cold hardiness calculator's number from the same weather stations, sharpened by our microclimate model for the ground right there. Zone is our MFTC zone, set by that one bad night, not by an average.

The weather stations behind it

These are the long-record stations in and around this map, with each one's own numbers since the winter of 1995-96. The last column is this map's 30-year number right at the station, which won't match the station exactly: it's a blend of the stations around it, the way the calculator works everywhere.

Source: NOAA records through ACIS, winters 1995-96 through 2025-26. What the "carried forward," "gaps filled" and AWOS rows mean is explained in how our microclimate maps work.