Fruit Trees for Watertown, Carthage and the Tug Hill Edge, New York

On January 22, 2014, NOAA's station at Watertown International Airport, out on the flat lake plain west of the city, bottomed out at −37°F. The downtown Watertown station, about 190 feet higher and 8 miles away, read −25°F in the same cold snap. That 12°F gap is what picking fruit trees for Watertown, Carthage and the Tug Hill edge comes down to. In this corner of the North Country, where your lot sits on the land matters as much as which town it's in.

The map covers the middle of Jefferson County, from Sackets Harbor and Dexter on eastern Lake Ontario up the Black River Valley to Carthage, north to Evans Mills and Philadelphia, and south onto the Tug Hill slope at Adams Center and Rodman. 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 at any spot is its 30-year planning low, the bad winter night we'd plan a tree around, the same kind of number our cold hardiness calculator uses. It runs cautious: a safe number to plan for, not a promise of how often that night comes. The MFTC zone is that number in half zones. The typical winter is an average year's coldest night, the kind of number USDA's map is built on, which is why USDA's zones read warmer than ours. The spring layer shows how many degrees warmer or colder a spot runs than downtown Watertown on a still, clear night at bloom.

The middle of the growing ground plans for −35°F (MFTC 3a), the coldest 5 percent for −39°F or colder and the warmest 5 percent for −32°F or warmer. Downtown, the reference town, plans for −31°F (MFTC 3b, typical winter −17°F). Dry Hill and East Watertown, just south and east of the city, plan for −30°F; Dexter and Paddy Hill, down on the lake plain, plan for −41°F (MFTC 2b). The downtown station hasn't read colder than −29°F since the 1995-96 winter, 2°F milder than its planning low, but it read −33°F in January 1994.

Why the map looks the way it does

The Black River is the spine of this map. It passes Carthage at 768 feet, turns west past Great Bend and Black River village, drops 120 feet over 2.5 miles through Watertown, then runs through a canyon to Dexter and Black River Bay, about 246 feet above sea level. South of the river the land climbs in terraces toward the Tug Hill, a tilted, flat-topped shelf of rock that rises from 250 to 350 feet at its western edge to 2,000 to 2,100 feet in the east. West and north of the city it's flat or gently rolling: the lake plain around the airport, the Perch River marshes and the sand of Fort Drum's Pine Plains.

On a clear, calm winter night the lake plain is where the cold gets made. NOAA station records show the airport, at about 311 feet, running a median 6°F colder than downtown on the year's coldest night, over 69 years. A 2012 study by Stephen Vermette of Buffalo State and David Zaff of the National Weather Service in Buffalo found the airport isn't in a bowl; it sits on a gentle grade toward Black River Bay, and drainage off the Tug Hill is a minor player. The air over the snow cools in place under a strong inversion: on January 14, 2009 it fell about 0.23°F a minute for an hour before dawn, to −23°F. Between 6 feet and 1 foot above the snow the temperature often differed by more than 10°F. On January 16 and 17, 2011, the airport hit −24°F while Black River village read −13°F, Adams −11.5°F and Cape Vincent, on the lake shore just west of the map, −2.5°F. Our map runs the plain at −38°F to −41°F.

The city sits above all that at about 470 to 500 feet, and it's built up. Masonry and pavement store heat and buildings hide the sky, which counts most on the still, clear nights that set the airport's records. Downtown plans for −31°F, the same as the benches within 3 miles, while the floor there plans for −34°F. Climb south and east and it holds, up to Dry Hill, 400 feet above its floor, at −30°F. That's the thermal belt, and it has limits. Around Sackets Harbor and Chaumont there's little bench ground, and it plans only 1°F to 2°F warmer than the floor. The Tug Hill top isn't a sure thing either. Hooker, at 1,478 feet, read −23°F in January 2014 while the airport read −37°F, but in January 2011 Constableville, at 1,763 feet, read −30°F, colder than the airport. Flats up high make their own cold, and Copenhagen and Clark Corners, near 1,200 feet, plan for −36°F and −37°F.

Draws streak cold through the slope. Rodman's streams have cut long ravines into the soft shale, and Zoar, in a draw, reads 10°F colder than downtown at bloom. Rutland Hollow, an abandoned bed of the Black River running past Watertown toward the lake, is the kind of long trough that carries cold, though we haven't found frost reports from it. Water helps less than you'd think. Lake Ontario rarely freezes over, but a lake shelters its shore only while it's relatively free of ice, and the bays here freeze (the state lists Black River Bay, Chaumont Bay and shallow Perch Lake among the county's top ice-fishing waters). There's no long-record NOAA station on the shore inside the map, so shore numbers lean on the airport and downtown records and run on the safe side. And on windy or cloudy nights the whole pattern flattens or flips; the January 1957 snap fits that, with downtown at −32°F and the airport at −30°F.

Downtown Watertown and the city neighborhoods

Watertown grew up on the falls, where the river drops 40 feet through the center of the city. Downtown and Public Square, at about 470 to 500 feet and roughly 70 feet above the nearby floor, plan for −31°F (MFTC 3b, typical winter −17°F). Within 3 miles the warmest tenth of growing ground plans for −30°F and the coldest tenth −36°F, a 6°F spread inside the city's reach. Of the six neighborhoods in the city's 2019 plan, Knickerbocker climbs to Thompson Park, on a hill about 725 feet up, roughly 260 feet above the city center. That's textbook thermal-belt ground, and East Watertown, a bench at about that height east of town, plans for −30°F. Northside has creeks and acres of wetland, the Sand Flats has the Beaver Meadows wetland, and the south end of Sherman holds about 60 acres of state-regulated wetland. Low, wet ground is where a still night's cold settles first, so check your own address there.

For a city lot, everything rated −35°F and colder clears with room: Honeycrisp (−45°F) and Empire apples, Seckel pear, Superior and Italian plums, Lapins sweet cherry and Siberian C peach (all −35°F). Trees rated −30°F, like Contender peach and Rainier cherry, are worth a try a few feet out from a south or west wall.

Watertown Center, East Watertown, Burrville and Dry Hill

The south and east side of the town of Watertown holds the warmest ground we found. Watertown Center, the town seat on US 11, sits on a terrace at 596 feet and plans for −31°F (MFTC 3b, typical winter −17°F), 1°F warmer than downtown at bloom. East Watertown, on NY 126 at 753 feet, and Dry Hill, the ski hill at 935 feet, plan for −30°F, the warmest named places we checked, with bloom nights 3°F and 6°F warmer than downtown. Underwood Hill, in southwest Rutland at about 1,135 feet, plans for −31°F and reads 8°F warmer at bloom, the best spring reading of any named place we checked (tied with Ward Hill). Burrville, at the falls on the North Branch of Sandy Creek, plans for −32°F, and so does Huntingtonville, down by the Black River, though it reads 5°F colder than downtown at bloom.

This is the ground for early bloomers: Westcot (−45°F) and Debbie's Gold (−50°F) apricots, Gold and Lapins sweet cherries (−35°F) and Toka plum (−45°F). Contender and Rainier clear −30°F with nothing to spare. Plant on the slope, not the hilltop, where wind strips the snow off the roots.

Glen Park, Brownville, Dexter and the airport plain

Below the city the river runs through its canyon past Glen Park and Brownville and comes out at Dexter, once called Fish Island, at 282 feet on Black River Bay. This is the bottom of the map. Glen Park and Brownville plan for −39°F (MFTC 3a) and read 4°F to 5°F colder than downtown at bloom. Dexter plans for −41°F (MFTC 2b, typical winter −25°F), with the coldest tenth of ground within 3 miles at −42°F. Limerick, by the Perch River, plans for −40°F; Paddy Hill, in a draw, plans for −41°F and reads 8°F colder at bloom; and the map reads −41°F at the airport station, whose record is −43°F (January 16, 1994).

The way out is up, even a little. Doanes Hill, about a mile and a half west of Dexter and 150 feet above its floor, still plans for −38°F, but on a bloom night it reads 5°F warmer than downtown, 9°F better than Dexter. That's where a plum, pear or apricot belongs down here. On the plain itself, plant what has come through −45°F and colder: Frostbite apple (−45°F), Kerr applecrab (−50°F), Evan's Bali tart cherry (−45°F), honeyberry and Montana Black Currant (−50°F). Snow covered the plain on every cold night the airport study looked at, and that's what protects the roots.

Sackets Harbor, Hounsfield and Chaumont on the bay shore

Sackets Harbor sits at 282 feet on Black River Bay, one of the few natural harbors on Lake Ontario. USDA's 2023 map puts it in zone 5b, the warmest of the ZIP codes around Watertown we checked. Our number is −37°F (MFTC 3a, typical winter −22°F), and it reads 4°F colder than downtown at bloom. USDA's zone is built on the average winter and ours on the bad night, and on the bad nights a frozen bay does little for its shore. Cape Vincent's −2.5°F that 2011 night fits what open water can do, so a lot right on the open lake may run milder than our number; plan on the number anyway. In Hounsfield, East Hounsfield and Camps Mills, on benches 110 to 160 feet up, plan for −36°F and −37°F and read only 2°F colder than downtown at bloom, while Alverson and Sulphur Springs plan for −38°F and −39°F and read 5°F colder. Down the shore, the Oswego, Fulton and Lake Ontario shore map picks up.

Chaumont, at 289 feet where the Chaumont River meets Chaumont Bay, plans for −36°F (MFTC 3a) and reads 4°F colder at bloom; the Pillar Point hamlet plans for −39°F. Luther Hill, between them and 140 feet above its floor, plans for −35°F and reads 2°F warmer than downtown, the best ground we found around Chaumont. The Chaumont Barrens alvar has soil only a few inches deep, so find the deepest you can. Along this shore pick from the −40°F list: Zestar! and Cortland apples, Luscious pear on the benches, Black Ice plum and La Crescent grape (all −40°F).

Black River, Calcium, Carthage and West Carthage

Upriver, Black River village (571 feet, once called Lockport) plans for −34°F (MFTC 3b, typical winter −19°F) and reads 4°F colder than downtown at bloom. Calcium, just west of Fort Drum, plans for −34°F but sits right at its floor and reads 9°F colder at bloom, while the benches within 3 miles plan for −31°F, so a little height pays off fast. Felts Mills and Deferiet, by the river, plan for −35°F and −36°F and read 6°F colder at bloom. Fort Drum's airfield station has a 30-year number of −32°F.

Carthage, the old Long Falls, sits at 768 feet with West Carthage across the river. Both plan for −34°F (MFTC 3b, typical winters −20°F and −19°F) and read even with downtown at bloom; within 3 miles the floor plans for −36°F and the benches −33°F. The flats upriver pool hard: Castorland, east of the map at 755 feet, read −24.7°F that January 2011 night, as cold as the airport. The hills are the good ground. Ward Hill, about 3 miles north, plans for −33°F and reads 8°F warmer than downtown at bloom, and Champion, on a hillside 220 feet above its floor, plans for −33°F and reads 4°F warmer. Put Morden 604 (−45°F) and Westcot apricots and Lapins and Gold sweet cherries (−35°F) up there.

Evans Mills, Philadelphia and the north end

North of the river it runs cold. Evans Mills, on the floor of the West Creek valley at 414 feet, plans for −37°F (MFTC 3a) and reads 6°F colder than downtown at bloom. Philadelphia, at the Indian River falls, is the cold spot of the old records. Its station, kept from 1908 to 1933, ran a median 7°F colder than Watertown's on the year's coldest night, and in the December 29, 1933 cold snap it read −47°F, the coldest December reading on record in New York State, while Watertown read −39°F. We haven't found a published explanation. The map plans it for −39°F (MFTC 3a, typical winter −24°F). Rivergate, in a river bottom, plans for −37°F and has the coldest spring reading of any named place on the map, 12°F colder than downtown. Plant from the −40°F and colder list up here. Farther north, the Canton, Potsdam and North Country map takes over.

Adams Center, Rodman and Rutland on the Tug Hill slope

South of the city the land climbs toward the Tug Hill in terraces. Adams Center, on a terrace at 633 feet, plans for −34°F (MFTC 3b, typical winter −19°F) and reads 1°F warmer than downtown at bloom, and Honeyville, 150 feet up, plans for −34°F and reads even. North Adams, right on its floor, plans for −35°F and reads 7°F colder. Rodman has deep, rich shale soils, and Sandy Creek and Stony Creek carry its cold west toward the lake on a still night. Rodman hamlet plans for −35°F and reads 6°F colder at bloom, and East Rodman, in a draw, reads 7°F colder. Dillen, on a bench 270 feet up, plans for −33°F, and so does Rutland Center, 180 feet up, though it reads 7°F colder at bloom, so a bench isn't a free pass in spring. The benches take anything rated −35°F and colder, and Summercrisp pear (−40°F) belongs up there; the floors and draws want −40°F and colder, like Titania black currant (−40°F).

Spring frost and bloom around Watertown

NOAA station records for 1991 to 2020 put downtown's median last 32°F frost on May 2 and its last 28°F on April 22, with a 159-day frost-free season. At the airport the last 32°F is May 14, the last 28°F April 29, and the season 138 days. One year in ten the last 32°F comes as late as May 14 downtown and May 29 at the airport. Lowville, just off the map's east edge at 863 feet, runs like the airport, with 142 days.

Open blossoms of nearly every tree fruit start dying at about 28°F. On the spring layer the floors and draws read up to 12°F colder than downtown on a still bloom night and the hills up to 8°F warmer, and NC State's fruit people figure 3°F to 4°F can separate no crop from a full one. We saw that in Montana's bloom freeze this spring, when growers low in the Missoula valley got hit hard and those up on the benches fared much better.

Spring 2012 is the local test case. After warmth near 80°F in March pushed buds early, frost came five nights running from April 26, with lows in the mid-20s°F. Cornell Cooperative Extension in Jefferson County said the north country got off lightly next to western New York. Thousand Islands Winery, just north of the map, bottomed out at 26°F; growers there put grape-bud damage at about 23°F to 25°F, and Coyote Moon in Clayton held off pruning six weeks to delay budbreak.

So put apricots, peaches, sweet cherries, plums and pears where the spring layer reads warm, and leave the floors and draws to apples, which need only about 15 percent of their blossoms to set a crop, to haskap, whose open flowers take 19°F, and to currants. Along the lake shore, lake breezes hold bloom back. Through bloom, mow short, don't till, and water a day or two before a frost. Fall matters too: the airport's median first 28°F is October 10, two weeks ahead of downtown, and a freeze before trees harden off kills at temperatures they'd shrug off in January, so we taper water from mid-August.

What the weather records say

The coldest readings in NOAA's station records here: Philadelphia −47°F (December 29, 1933), the airport −43°F (January 16, 1994), Lowville −40°F (December 20, 1942), downtown −39°F (December 29, 1933), the old Adams Center station −36°F (February 12, 1917) and Hooker −29°F (February 14, 2016, on 11 years). The big cold snaps split the same way: in January 1994 the airport read −43°F and downtown −33°F, and in February 2016, −37°F and −29°F.

NOAA station records show the worst night in about 30 winters runs a median 13°F below a station's average winter low, which is why USDA's 2023 zones, built on averages, read warmer than ours: 5b at Sackets Harbor, 5a at Watertown, Dexter, Adams Center and Philadelphia, and 4b at Black River, Carthage and Rodman. On our planning low, downtown, Carthage and Adams Center are 3b, Sackets Harbor and Philadelphia 3a, and Dexter 2b. Downtown averages 116.4 inches of snow a year, the Tug Hill more than 200, and Hooker holds New York's single-season record, 466.9 inches in 1976-77.

What you can grow here

Most apples, pears, plums and sweet cherries need a second variety nearby, and our pollination maps show which pollenizers pair up.

City lots and the hills south and east of town, −30°F to −33°F (downtown, Watertown Center, East Watertown, Dry Hill, Ward Hill, Dillen): everything rated −35°F and colder fits, like Honeycrisp apple, Seckel pear, Superior and Toka plums, Lapins sweet cherry, Westcot apricot, Siberian C peach and Marquette grape (−35°F). Liberty apple and Contender peach (−30°F) are worth a try on the warmest lots.

The upriver villages, the Tug Hill slope and the bay shore, −34°F to −37°F (Carthage, Black River, Calcium, Adams Center, Rodman, Chaumont, Sackets Harbor, Evans Mills): pick from the −40°F and colder list, like Haralson and Wolf River (−45°F) and Zestar! and Cortland (−40°F) apples, Luscious pear (−40°F) on the benches, Black Ice plum (−40°F), Meteor tart cherry (−40°F), Morden 604 apricot (−45°F) on hillsides that read warm at bloom, and La Crescent grape (−40°F). Trees rated −35°F, like Lapins and Siberian C, fit the −34°F and −35°F towns and are worth a try down to −37°F.

The lake plain and the cold bottoms, −38°F to −42°F (Dexter, Limerick, Brownville, Glen Park, Philadelphia, the airport): stick to what has come through −45°F and colder, like Frostbite (−45°F) and Wealthy (−50°F) apples, Kerr (−50°F) and Trailman (−60°F) applecrabs, Evan's Bali tart cherry (−45°F), Romeo dwarf cherry (−50°F), Krasnobokaya pear and Brookred plum (−50°F) only on rises like Doanes Hill, and honeyberry and Montana Black Currant (−50°F) anywhere. Trees rated −40°F are worth a try on the higher spots at −38°F to −40°F.

Roots are the weak link everywhere here. Cornell's fruit people rate G.935 very hardy, G.16, G.30, G.41, B.9 and M.26 hardy, M.9 and MM.111 moderately hardy, and M.7 cold sensitive. In a 2004 Northern New York freeze G.16 came through while many M.9, B.9 and M.26 trees died, and in a Champlain Valley trial that January, lows near −25°F with no snow killed roots on several Malling stocks. At Ed Schultz's farm in Gallatin Gateway, Montana, Bud 118 rootstock has seen near −50°F with no damage, under snow. So hold snow over the roots, keep the soil moist going into winter, and on any ground the wind scours, use the hardiest stock you can get.

Site the trees the way Bob Purvis taught us: an east-facing slope is ideal, off the valley bottom but not on a windswept hilltop, with brush cleared below so cold can drain away. Montana State recommends a 4 to 8 percent grade. Give them at least 6 hours of direct sun (8 to 10 is better), and test drainage first: dig 2 feet, fill it, let it drain, fill it again, and under 10 hours is well drained. That matters on the heavy clays and on the thin limestone soils of the north end, which flood in spring and dry out in summer. For scab and fire blight, Cornell names Freedom and Liberty for scab resistance, Honeycrisp and Liberty for fire blight, and Seckel among the pears for fire blight. Stanley plum is highly susceptible to black knot, so lean on Toka, Superior and Black Ice here.

Fruit history here

Jefferson County was dairy and grain country (barley led by 1860), and neither the 1860 nor the 1890 county gazetteer we read mentions orchards. The fruit landmark is the Burrville Cider Mill, built in 1801 on Burrville Falls and pressing cider since the 1800s, with apples bought from nearby orchards. Grapes are the newer story. The Thousand Islands area around Watertown and the St. Lawrence Seaway is one of three North Country grape regions, growing hybrids that survive about −40°F.

Questions people ask

What growing zone is Watertown, NY?

USDA's 2023 map puts Watertown (ZIP 13601) in zone 5a, −20°F to −15°F, though some older sources still say 4b. That's built on an average winter's coldest night. On the bad night we plan for, downtown Watertown is −31°F, MFTC zone 3b, and the lake plain around the airport and Dexter runs 2b to 3a.

When is the last frost in Watertown, NY?

NOAA station records for 1991 to 2020 put the median last 32°F frost on May 2 downtown and May 14 at the airport. One year in ten it comes as late as May 14 downtown and May 29 at the airport. The last 28°F, where open blossoms start dying, comes around April 22 downtown and April 29 at the airport.

Why is the Watertown airport so much colder than the city?

It sits on open, nearly flat lake plain, where snow-covered ground cools fast on clear, calm nights under a shallow inversion. A 2012 study found the air there cools in place rather than draining in from the Tug Hill. NOAA station records show it runs a median 6°F colder than downtown on the year's coldest night, and it ran 12°F colder in January 2014.

Does Lake Ontario protect Sackets Harbor from frost?

Some. USDA puts Sackets Harbor in zone 5b, the warmest of the ZIP codes around Watertown we checked, but Black River Bay freezes most winters, and a frozen bay doesn't warm its shore. Our planning low there is −37°F (MFTC 3a), and the village reads 4°F colder than downtown Watertown on a still bloom night.

Can you grow peaches in Watertown?

Yes, with the right tree on the right ground. Siberian C has come through −35°F, which clears downtown's −31°F, and Contender (−30°F) is worth a try in a sheltered city spot and clears East Watertown and Dry Hill at −30°F. Plant them where bloom nights read warm, like Dry Hill (6°F warmer than downtown), not on the airport plain.

Can you grow grapes around Watertown and the Thousand Islands?

Yes, with cold-hardy hybrids. Thousand Islands growers use varieties that survive about −40°F, like Marquette, Frontenac and La Crescent, while vinifera is often killed by subzero cold. Our La Crescent (−40°F) suits most of this map, and Marquette and Frontenac (−35°F) clear the city and the Tug Hill benches.

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.