Fruit Trees for Houghton, Hancock and the Keweenaw, Michigan

On February 27, 2015, the NOAA station at Jacobsville, on the Keweenaw Bay shore south of Houghton, read −26°F, the coldest in its 12 years on file. Copper Harbor, out at the tip of the peninsula, bottomed out at −9°F that morning. That 17°F spread is the first thing to understand about fruit trees for Houghton, Hancock and the Keweenaw: Lake Superior wraps the north end in open water, and the waterway, the bays and the low country at the base of the peninsula don't get the same help.

This map covers the Copper Country from Chassell and Jacobsville north through Houghton, Hancock and Torch Lake, the ridge towns from Painesdale to Calumet and Mohawk, and the north end at Eagle River, Eagle Harbor and Copper Harbor. 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, the same number our cold hardiness calculator uses, built from NOAA station records and the lay of the land. It leans cold: a safe number to plan around, not the record. 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 zones are built on. The spring layer shows how many degrees warmer or colder a spot runs than Houghton on a still, clear night at bloom.

Houghton plans for −30°F (MFTC 4a) with a typical winter of −15°F. The middle of the growing ground plans for −27°F, and half of it falls between −30°F and −26°F. The warm end is the tip, where Copper Harbor plans for −17°F (MFTC 5a). The cold end is the flat country around Pike Bay: Best, half a mile south of Chassell, plans for −32°F (MFTC 3b).

Why the map looks the way it does

Lake Superior is the biggest thing on this map. Its deep water stays near 39°F all year and it rarely freezes over completely, so on a winter night it's a heat source; Illinois State Water Survey researchers put its lift on mean winter lows at up to 14.4°F. The tip has open lake on three sides and gets the most of it. The long Houghton County record has run a median 5°F colder on the year's coldest night than Eagle Harbor on the north shore, and on February 9, 1951, when Houghton County hit its all-time low of −30°F, Eagle Harbor read −15°F. Average yearly lows step down from −5°F at Copper Harbor to −10°F at Eagle Harbor and −15°F at the airport and Jacobsville. The Marquette, Ishpeming and Negaunee map shows the same lake at work 60 miles east.

Portage Lake, Torch Lake and the rest of the Keweenaw Waterway are a different story. They freeze (in 2020 Torch Lake was iced over by about December 17), and lakes shelter their shores only while they're relatively free of ice, as Wisconsin's state climatologists put it. Once frozen, they're flat floors at the bottom of a valley. Keweenaw Bay isn't reliable either: on February 28, 2014, Jacobsville read −24°F to Copper Harbor's −13°F, and no source we found explains why. Just south of the map, at the head of the bay, Baraga hit −41°F on February 17, 1979, a morning the airport read −21°F.

The spine of the peninsula is a flat-topped ridge about 500 to 600 feet above Lake Superior, cut by low gaps. The deepest is the Portage Lake valley, where Houghton and Hancock face each other from bluffs about 500 feet high. On a clear, calm night the chilled air slides off the ridge and settles on the lowest ground: the waterway, the Torch Lake basin, and the Pike Bay flats where the Sturgeon River's lower valley, the main low corridor into the map from the south, comes in at Chassell. Within 3 miles of Houghton the floor plans for −32°F and the benches −28°F; a Hungarian study of 69 clear, calm nights found a valley floor averaged 6.7°F colder than a slope 230 feet higher, and the waterway is that kind of floor.

Up on the ridge the cold has somewhere to go, which makes it the Copper Country's thermal belt. Calumet sits on a broad upland with almost no floor within 3 miles, and the old Calumet station ran a median 3°F colder than Eagle Harbor, against 5°F for the Houghton County record. North of Calumet the ridge climbs into the Greenstone and Bohemia ranges, where steep peaks near the lake plan for −17°F to −20°F and read 11°F to 12°F warmer than Houghton on a still spring night (Mount Houghton, Brockway Mountain, Gratiot Mountain). That's a calm-night pattern; on a windy night higher ground runs colder, and Brockway's summit is semi-alpine and windy, so plant on the slope below a crest.

Then there's snow. The Copper Country gets more on average than anywhere in the U.S. east of the Mississippi: about 208 to 220 inches a year at Houghton and Hancock, about 240 at Delaware on the ridge, and only about 84 at Eagle Harbor. Snow chills the air above it but blankets roots, the weak link in any fruit tree; NDSU measured soil a foot down under snow at 31°F with the air at 4°F.

Houghton, Hancock and the waterway

Downtown Houghton, the sandstone blocks along Shelden Avenue, sits right at the water at 626 feet on the valley floor. It plans for −30°F (MFTC 4a) with a typical winter of −15°F, and it's the reference town for the spring layer. Cold air pours in off the hills on both sides, and in midwinter the frozen waterway is no help. The mining-era houses on the hill south of downtown do better: Hurontown, 270 feet above the floor, plans for −28°F and reads 6°F warmer than Houghton at bloom, and Dodgeville, 2 miles south, plans for −27°F and reads 3°F warmer. That hill faces north, and Bob Purvis's rule is that a north slope holds early bloomers like apricots and plums back. East Houghton along College Avenue and West Houghton's bigger lots run along the same shore; the number improves as you climb.

Across the lift bridge, Hancock climbs a south-facing hillside toward the old Quincy Mine. Downtown on Quincy Street, 60 feet above the floor, plans for −29°F (MFTC 4a) and reads 4°F warmer than Houghton at bloom, because cold air slides past on its way to the water. Franklin Mine, a mile up the hill and 510 feet above the floor, plans for −26°F and reads 7°F warmer, and Arcadian Hill, above Ripley, plans for −24°F (MFTC 4b) and reads 8°F warmer. Paavola, out on the flat upland, plans for −26°F but reads 3°F colder: a flat top makes its own cold and has nowhere to send it. On that south face a sunny trunk commonly runs about 36°F above the air on a bright winter day (the FAO's frost protection manual), so paint trunks with white interior latex cut half with water.

At −29°F to −30°F, Lapins and Gold sweet cherries (−35°F), Superior plum (−35°F) with Toka (−45°F) as its pollenizer (our pollination maps show the other pairings) and Bartlett pear (−35°F) all clear the waterfront. Contender peach (−30°F), the only commercial peach we know of that has taken −32°F, belongs up the hill.

Calumet, Laurium and the ridge up to Mohawk

Calumet (Red Jacket until 1929) sits at 1,209 feet on the broad top of the ridge, 130 feet above the nearest low ground. It plans for −26°F (MFTC 4a) with a typical winter of −12°F, and within 3 miles even the coldest tenth of the ground plans for only −27°F, because the ridge sheds its cold toward Torch Lake on one side and Lake Superior on the other. Laurium, 250 feet above its floor, plans for −25°F (MFTC 4b). At bloom the ridge splits up: Calumet's flat center reads 4°F colder than Houghton, while Tamarack, under a mile west, reads 5°F warmer and West Tamarack, on an 8 percent slope, 7°F warmer. Yellow Jacket and Blue Jacket, bordering Calumet, sit on the same upland.

North along US 41, Kearsarge plans for −26°F and reads 6°F warmer than Houghton at bloom, Bumbletown −24°F (MFTC 4b) and 7°F warmer, Mohawk about −25°F and 4°F warmer. The exception is the low ground at Ahmeek, Kingston and Copper City, which plans for −27°F to −28°F and reads 5°F to 7°F colder; Allouez, a mile from Ahmeek and 180 feet above its floor, reads 11°F warmer than Ahmeek on a spring night. Put Westcot apricot (−45°F) and sweet cherries on the slopes that read warm, and keep the Ahmeek bottom for apples, haskap and currants.

Torch Lake: Lake Linden, Hubbell and Dollar Bay

Torch Lake, about 6 miles long, lies below the east side of the ridge and drains south through Torch Bay into Portage Lake. Calumet sits 4 miles northwest of Lake Linden and nearly 600 feet higher, and on a still night the cold off that slope runs down to the lake. Lake Linden plans for −29°F (MFTC 4a) with a typical winter of −15°F and reads 4°F colder than Houghton at bloom. Hubbell, 2 miles southwest, plans for −29°F and reads 6°F colder, and Gregoryville, on the bottomland near Lake Linden, reads 7°F colder. Steep ground is the fix: Bunker Hill, on an 18 percent slope near Mason, plans for −28°F and reads 4°F warmer than Houghton. Dollar Bay, on its own inlet 3 miles east of Houghton, plans for −29°F and reads about even.

The mills dumped about 200 million tons of copper stamp sand into Torch Lake, and stamp sand also buried the Lake Superior beach at Gay. It's crushed rock, not soil: bring in topsoil and test drainage (a refilled 2-foot hole that empties in under 10 hours is well drained). Gay itself, on the open shore, plans for −23°F (MFTC 4b). Around Torch Lake, plant honeyberry (open haskap flowers take 19°F), currants and apples near the water, and apricots and sweet cherries only up the slope.

South Range, Atlantic Mine and Painesdale

The south end of the copper range runs about 3°F colder on the map than Calumet at about the same height. South Range, at 1,139 feet and 220 feet above its floor, plans for −29°F (MFTC 4a) with a typical winter of −14°F, and its center reads 4°F colder than Houghton at bloom. Atlantic Mine, 2 miles north, plans for −27°F and reads 5°F warmer, and Baltic −28°F and 4°F warmer. Painesdale, in a draw at 1,299 feet, plans for −29°F and reads about even. Tolonen Hill, south of Painesdale, plans for −28°F and reads 10°F warmer, if you stay off the windy top. The old USGS survey called the seasons short, especially on the higher Copper Range, so I'd skip Siberian C peach (−35°F) here: it has the hardiness, but it ripens very late.

Chassell, Pike Bay and the Keweenaw Bay shore

Chassell sits on Pike Bay, an inlet of Portage Lake near the mouth of the Sturgeon River, about 7 miles south of Houghton. It plans for −31°F (MFTC 3b) with a typical winter of −16°F; within 3 miles the floor runs −33°F and the benches −29°F. Best, on the flat half a mile south, plans for −32°F with a typical winter of −18°F. At bloom Chassell reads about even with Houghton, Best 3°F colder and Tapiola, inland on low ground, 5°F colder, while Klingville, 140 feet up, reads 2°F warmer. Strawberries flower close to the ground, which can run 4°F to 8°F below a thermometer 5 feet up, and Niemela Family Growers in Chassell irrigate partly against frost. Frost cloth of 0.5, 0.9 and 1.5 ounces per square yard gains about 4°F, 6°F and 8°F.

East of Chassell is the red sandstone country southeast of the Keweenaw Fault, softer rock worn down to lowland. Jacobsville plans for −30°F (MFTC 4a) and reads 1°F colder than Houghton at bloom; its station's own 30-year number is −30°F, colder than the −26°F it has actually recorded in 12 years. The first rise pays: Point Mills, 120 feet above its floor, plans for −28°F and reads 6°F warmer than Houghton. Down here plant for the cold, starting with Kerr or Trailman applecrab (−50°F and −60°F); if you only plant one tree, make it one of those.

Eagle River, Eagle Harbor and Central

Eagle River, the Keweenaw County seat, sits at the mouth of its river about 27 miles northeast of Houghton. It plans for −22°F (MFTC 4b) with a typical winter of −9°F, warmer than even the warmest tenth of the ground within 3 miles, and reads 3°F warmer than Houghton at bloom. The lake doesn't reach far inland: Phoenix, 2 miles inland at the junction of M-26 and US 41, plans for −26°F and reads 8°F colder at bloom, though it sits 180 feet above its floor. Central, 4.5 miles east of Eagle River on a hillside 280 feet above its floor, plans for −23°F (MFTC 4b) and reads 6°F warmer, with cold draining past instead of sitting, and that's where the Cornish apple trees still bear. Eagle Harbor, 7 miles up the shore, plans for −23°F (MFTC 4b) with a typical winter of −10°F, and Mount Lookout, 3 miles east of it, plans for −20°F and reads 11°F warmer at bloom.

Copper Harbor, Lac La Belle and Keweenaw Point

Copper Harbor, Michigan's northernmost community, plans for −17°F (MFTC 5a) with a typical winter of −5°F, reads 1°F warmer than Houghton at bloom, and has the longest frost-free season of the NOAA stations here, a median 161 days. Two cautions. The station read −21°F on March 3, 2003, 4°F colder than the planning number, so pick trees that have come through −25°F or colder. And the two stations, about a mile apart, don't agree. Fort Wilkins, beside Lake Fanny Hooe, carries its own 30-year number of −21°F to the harbor's −17°F; in February 2009 and February 2014 it fell to −18°F while the harbor stopped at −13°F, and its median last spring frost comes 13 days later. (They only overlap from 1999 to 2013.) The map reads them within a degree. It looks like the small lake basin collects cold the harbor front doesn't, so near Lake Fanny Hooe plan a few degrees colder.

Brockway Mountain, 4 miles west, plans for −18°F, and Lac La Belle, near Mount Bohemia, −20°F (MFTC 5a). Bete Grise plans for −19°F but reads 3°F colder than Houghton at bloom. Picking for −25°F, Blushingstar peach (−25°F), which came through −25°F at our place on January 13, 2024 without damage, fits close to a south wall in town, and if there's anywhere on this map to try Siberian C, it's the harbor's 161-day season.

Spring frost and bloom on the Keweenaw

The spring layer follows the same drainage as winter, because bloom frost comes on still, clear nights when cold air pools. Warmest at bloom are the north-end peaks and Tolonen Hill (10°F to 12°F warmer than Houghton) and hilltops near town like Arcadian Hill, Franklin Mine, West Tamarack and Bumbletown (7°F to 8°F warmer). Coldest are the Torch Lake basin, the low ground at Ahmeek and Nepco Camp Number 7, and inland Phoenix (4°F to 8°F colder), and Tapiola and Onkalos Corner (5°F colder).

Lake Superior also keeps its shore cool into spring and holds bloom back; at Copper Harbor, April is still a winter month. NOAA station records (1991 to 2020 medians):

• Houghton County Airport, on the upland at 1,063 feet: last 32°F frost May 16 (one year in ten June 3), last 28°F May 6, first fall 32°F September 30, 138 frost-free days.
• Copper Harbor: last 32°F May 7, last 28°F April 24, first fall 32°F October 19, 161 days.
• Fort Wilkins: last 32°F May 20, last 28°F May 2, first fall 32°F October 16, 150 days.

A first frost at the end of September means late apples and pears may not ripen on the upland, and trees have to harden off before the first hard freeze. We taper water from mid-August in zone 4 and colder and skip late nitrogen.

Open blossoms of nearly every tree fruit start dying near 28°F, but only about 15 percent of apple blossoms need to set for a crop, sweet cherries can lose about half their flowers and still crop fully, and haskap flowers take 19°F. We haven't found a documented spring freeze wiping out a Keweenaw crop, so the spring layer is the best guide. Put apricots, sweet cherries and peaches on ground that reads warm, apples and pears in between, and haskap and bush fruit in the cold spots. Through bloom, mow the grass short and water a day or two before a frost night.

What the weather records say

NOAA files the long Houghton County record under the airport's name and carries it back to 1892. Its coldest reading, −30°F, came on February 10, 1948 and again on February 9, 1951, and its average yearly low is −15°F. Its own 30-year number is −27°F, colder than anything it has recorded since 1995 (−25°F, in February 2014 and 2015). The old Calumet station bottomed out at −26°F on February 9, 1933; Eagle Harbor's record is −23°F (January 31, 1918), Fort Wilkins's −22°F (February 10, 1994) and Copper Harbor's −21°F (March 3, 2003).

USDA's zone map is built on the average of each winter's coldest night, and the Houghton County average of −15°F sits on the line between USDA 5a and 5b. Our planning low of −30°F puts downtown Houghton in MFTC 4a, more than a full zone colder, and that's normal: 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 on the Keweenaw

Every plant we sell is rated by the coldest temperature it's known to have come through; compare that to your number.

The tip and the Lake Superior shore, −17°F to −23°F

Copper Harbor, Lac La Belle, Eagle Harbor, Eagle River, Central and Gay. With −21°F and −22°F on record at Copper Harbor, pick for −25°F: Blushingstar peach on a south wall, Contender peach and Harlayne apricot (−30°F) on slopes, Rainier and Stella sweet cherries (−30°F), D'Anjou pear (−30°F), Shiro plum (−30°F) and Liberty apple (−30°F).

The ridge and the hills above town, −24°F to −27°F

Calumet, Laurium, Mohawk, Allouez, Kearsarge, the hills above Houghton and Hancock, and Atlantic Mine. Lapins, Gold and Rainier sweet cherries; Westcot and Sungold (−40°F) apricots on slopes that read warm at bloom; Superior with Toka, and Italian plum (−35°F); Bartlett and Seckel (−35°F) pears; Honeycrisp (−45°F) and Zestar! (−40°F) apples.

Houghton, Hancock, Torch Lake and the south range, −28°F to −30°F

Downtown Houghton and Hancock, Dollar Bay, Lake Linden, Hubbell, South Range, Painesdale and Jacobsville. Lapins and Black Gold (−35°F) sweet cherries on your warmest ground; Superior, Toka and Mount Royal (−40°F) plums; Ure and Summercrisp (−40°F) pears; Evan's Bali (−45°F) and Meteor (−40°F) tart cherries; Honeycrisp, Haralson and Spartan (−45°F) apples.

Chassell, Pike Bay and the coldest floors, −31°F to −34°F

Chassell, Best, Tapiola and the low ground along the Sturgeon. Kerr and Centennial applecrabs (−50°F; Ed Schultz saw zero winter injury on Centennial after a winter that hit −47°F), Haralson, Frostbite (−45°F) and Wealthy (−50°F) apples, Krasnobokaya (−50°F) and Ure pears, Toka and Brookgold (−50°F) plums, Evan's Bali and Juliet (−50°F) cherries. Superior and Lapins (−35°F) clear it by a degree or more; give them the first rise off the floor.

Berries, anywhere on the map

Honeyberry (−50°F), Montana Black Currant (−50°F), Red Lake currant (−40°F), Boyne red raspberry (−40°F), Aronia (−50°F), and for strawberry country Honeoye (−50°F) and AC Wendy (−40°F). Red Lake fruited well for us in 2026 after its flower buds saw about 22°F.

Snow is your friend for roots: Geneva rootstocks came through −40°F unhurt under about 6 inches of snow in 1994, and Bud 118 has seen near −50°F under snow at Ed Schultz's farm in Gallatin Gateway, Montana, with no rootstock damage. Where snow runs thin, on the north shore and windblown crests, use the hardiest stock and mulch. Plant on a slope, off the floor and the windswept crest (Montana State recommends a 4 to 8 percent grade), and open any hedge across the slope below your trees so it doesn't dam cold air. Watch for deer, which treat pressed apple pulp like bait, and for voles, which a grower at Sault Ste. Marie reports tunneling under deep lake-effect snow to girdle trees; guard trunks before the snow comes.

Fruit history in the Copper Country

The best proof of what grows here is at Central. The Cornish miners who settled that mine town (the Central Mine ran from 1854 to 1894) left tens of thousands of apple trees, some about 150 years old, and people still harvest them every October, shaking the fruit onto tarps. Central and Copper Harbor both hold fall cider pressings; in 2019 one of the trees pressed at Copper Harbor was a Sheepsnose type apple with pinkish flesh, one of six picked out of about 200 tasted for a possible heirloom orchard.

Chassell is the Strawberry Capital of the Upper Peninsula. Strawberries took hold there early in the 20th century as lumbering declined, and by the 1920s growers had saturated the local market. After trips to Bayfield, Wisconsin, to learn shipping, they formed the Copper Country Strawberry Growers Association in 1936 and shipped about 5,000 cases by rail to Milwaukee, Chicago and Green Bay the first year. The first Strawberry Festival opened July 6, 1949. MSU's 1958 variety bulletin rated Red Lake the hardiest currant.

Questions people ask

What growing zone is Houghton, Michigan?

Downtown Houghton plans for −30°F on our map, MFTC zone 4a, with a typical winter of −15°F; the hills south of town plan for −27°F to −28°F. USDA's zones are built on the average winter, ours on the bad night. We couldn't confirm USDA's 2023 zone, but the Houghton County record's average yearly low of −15°F sits on the line between USDA 5a and 5b.

When is the last frost in Houghton, MI?

At the Houghton County Airport the median last 32°F frost is May 16 and the last 28°F May 6 (NOAA station records, 1991 to 2020), and one year in ten the last 32°F comes as late as June 3. The first fall frost comes around September 30. Copper Harbor's median last frost is May 7.

Where are the frost pockets around Houghton and Calumet?

On still spring nights the Torch Lake basin is the big one: Gregoryville and Hubbell read 6°F to 7°F colder than Houghton. On the ridge, the low ground at Ahmeek, Kingston and Copper City reads 5°F to 7°F colder. In winter the coldest ground is the Pike Bay flats around Chassell, where the floor plans for −33°F.

Can you grow apples in the Keweenaw?

Yes. Tens of thousands of apple trees the Cornish miners planted at Central still bear, some about 150 years old. Anywhere on this map, Honeycrisp, Haralson and Frostbite (−45°F) and Kerr applecrab (−50°F) have room to spare, even at Chassell's −31°F.

Why is Copper Harbor warmer in winter?

Lake Superior is open water on three sides of the tip, and open water is a heat source on a winter night. The Copper Harbor station's average yearly low is −5°F, against −15°F for the Houghton County record, and our map plans for −17°F there (MFTC 5a). It isn't guaranteed: the station read −21°F on March 3, 2003.

How much snow does Houghton get, and is it good for fruit trees?

About 208 to 220 inches a year at Houghton and Hancock, about 240 at Delaware on the ridge and about 84 at Eagle Harbor. That's mostly good for fruit trees, since snow insulates roots, the least hardy part of a tree; just guard trunks against voles.

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.