Wisconsin Ledge is an American Viticultural Area (AVA) on the edge of Lake Michigan, in the northern US state of Wisconsin. Covering 3800 square miles (9850 sq km), the area is home to 14 wineries and just over 300 acres (120ha) of vineyard. The climate is heavily moderated by the proximity of several large bodies of water, and Franco-American hybrid grape varieties such as Frontenac, Niagara and Marechal Foch do best in this cool-climate region.
The AVA covers a peninsula in the north-eastern corner of Wisconsin that extends for around 140 miles (225km) into Lake Michigan. Green Bay lies on the western side of the peninsula, and the much smaller Lake Winnebago can be found in the south-western corner of the AVA. Wisconsin Ledge is named for what locals refer to as 'the Ledge': actually the westernmost portion of the 650-mile-long (1050km) Niagara Escarpment landform that runs through the Great Lakes region before reaching Wisconsin. The escarpment is most famous as the cliff that forms the Niagara Falls, but it is also home to wine production in both New York and Ontario.
© Wikimedia/Royalbroil
The topography of Wisconsin Ledge is the result of ancient glacial movement. The land on the peninsula slopes gently upward from the shores of Lake Michigan to the top of the Ledge, before dropping sharply off into Green Bay. Most of the vineyards lie on these eastern-facing slopes that benefit from constant air movement from Lake Michigan, which stores warmth during the summer. The presence of the lake produces a vacuum of sorts during the growing season: warm air over the lake rises, sucking colder air off the land and creating offshore breezes. Cold air cannot settle over the vineyards and there is a constant flow of warmer air, making the growing season here longer than in other parts of Wisconsin.
Wisconsin Ledge's glacial soils are made up of gravel, sand and clay over limestone bedrock. These are well drained, with poor fertility, making them excellent for growing grapes. A lack of water in the ground leads to vines with lower yields and vigor, resulting in the production of high-quality grapes. An aquifer below the AVA provides mineral-rich groundwater to the vines, encouraging deep root growth. This aquifer maintains a consistent temperature, which warms the ground in early spring and late fall, causing fog that helps to protect vineyards from devastating frosts.
The Wisconsin Ledge AVA, approved in 2012, became the state's third after Lake Wisconsin and the gargantuan Upper Mississippi Valley, which also covers land in Minnesota, Iowa and Illinois. At present, there are no wines using the Wisconsin Ledge AVA, but this is likely to change in coming vintages. Wineries in the area include Stone's Throw, Simon Creek Winery and Trout Springs Winery.
