The maples of northern Vermont were just beginning their ignition to orange as my wife and I drove along an unpaved road on the shoreline of South Hero, an island in Lake Champlain 30 minutes north of Burlington. On that last weekend of September, it was already fleece-wearing weather.

“I think I just saw a sign for a winery ahead,” my wife said.

“No, dear, we’re too far north for a winery,” I intoned. “Vines would never survive the winter up here.”

Ten minutes later, having swallowed my doubter’s words, I was sipping a light-bodied, citrus-edged Sevyal Blanc in the steep-roofed tasting room of Snow Farm Winery, which describes itself as “Vermont’s first grape winery and vineyard.” Outside, 12 acres of vines, some already harvested but most still laden with the 2006 vintage, stretched in long rows toward the lake. On the far side, the peaks of New York’s Adirondacks loomed.

“You’re not the only one to assume that we’re too far north to grow wine grapes here,” Snow Farm’s co-proprietor, Harrison Lebowitz, told me. “But being here in the middle of Lake Champlain, which stays warm well into the fall, we actually have a growing season that is almost a month longer than elsewhere in Vermont. We’re like the Finger Lakes in New York, even though they’re farther south.”

Mr. Lebowitz’s explanation of Snow Farm’s protected place in the northland was regularly interrupted by the blast and hiss of a decompressing bladder press in the adjacent winery. “That’s our 2006 Estate Sevyal Blanc being pressed,” he said. Snow Farm makes 3,100 cases a year of eight different wines. Some are mainstream classics like chardonnay ($16.95), while others are hybrids ranging from the dry Seyval Blanc ($12) to a surgingly sweet, acid-braced Vidal ice wine ($45).

My favorite of six wines tasted was the deep red Leon Millot. It was instructive to taste this last wine in two versions: an unoaked version made from Finger Lakes grapes (the only Snow Farm wine not grown in its own vineyards) and an estate version that had been aged for two to three months in American oak barrels. The Finger Lakes version ($12.50) was all pungency and blunt energy, ready to partner with autumn’s first hearty beef stew. The estate version ($13.50), on the other hand, was spicier and smoother, and the better wine by far. Mr. Lebowitz spoke glowingly of his pinot noir, claiming that his location is ideal for growing this finicky grape. It’s made by winemaker Patrick Barrelet, who was credentialed in Dijon, France. Alas, each vintage of pinot noir sells out quickly, and none was available to taste.

Mr. Lebowitz and his wife, Molly, a real estate lawyer, moved to Vermont from New York in 1990, intent on finding a better place to raise their children. “We saw that many old farms were being sold for housing and sprawl was developing,” Mr. Lebowitz said. “This property had been a dairy farm and when it was put up for sale, I wondered about preserving it as open space by creating a vineyard. My wife is usually skeptical about my wild ideas, but this time she said, ‘Go for it.’ Luckily, an explosion of cold-climate vineyard research had occurred in the 1980s. After three years of investigating, I concluded that we could succeed in South Hero.” Snow Farm opened its tasting room in 1997 and Mr. Lebowitz gave up his job as a state prosecutor specializing in child abuse cases to manage the winery full time. The name the couple picked for the winery, he explained, combines “two things which are the essence of Vermont. Besides, Ernest and Julio Lebowitz didn’t quite work.”

Various strategies are employed to fend off vine damage from the winter’s worst freezes. Most vines are trained low to the ground, where the temperature is typically warmer than the air a few feet higher due to the radiant heat of earth and snow. Shoots of the vinifera vines of European origin, more delicate than the hybrids, are painstakingly fitted with tubes normally used for insulating pipes. And, since South Hero typically gets more rain than the vines need, tiled channels in the earth have been created to carry off excess water.

Snow Farm offers concerts on its broad lawn every Thursday evening in summer. In May, it arranges “Apple Blossom” bike tours for visitors, including an alfresco lunch at the winery. “We do whatever we can to answer the question, ‘How do you get people to come down a dirt road to prove you can grow wine grapes in Vermont?'” Mr. Lebowitz says. With autumn colors set for full glory, next weekend would be a great time to take that road.

Snow Farm Vineyard, 190 West Shore Road, South Hero, Vt., 802-372-WINE, snowfarm.com. Open daily for tours and tastings, 10 a.m.–5 p.m., through December 31.