Upper Mississippi Valley AVA
The Upper Mississippi River Valley AVA is an American Viticultural Area covering 29,914 square miles (77 477 square kilometers) located along the Upper Mississippi River and its tributaries in northeast Iowa, northwest Illinois, southeast Minnesota and southwest Wisconsin. Upon its approval on June 22, 2009, with the effective date of July 22, 2009, it became the world's largest designated appellation. The boundaries of the AVA share the unique geographical connection of all being part of the Paleozoic Plateau, also known as the Driftless Area, and therefore do not have the same type of vineyard soils as wine regions that were in areas that have experienced glaciation in their history.
The first winery, Alexis Bailly Vineyard and Winery, in the area was opened in 1973 near Hastings, Minnesota. At the time it was believed that this part of the Upper Mississippi Valley endured winters that were too cold to sustain viticulture. Many of the areas within the Upper Mississippi River Valley AVA used to support tobacco farming. As smoking fell out of fashion in the late 20th century and farmers began to lose their federal government subsidies, alternative agricultural options were explored. An agricultural extension agent from Vernon County, Wisconsin proposed the idea of tobacco farmers replacing their crops with wine grape varieties.
Climate and geography 
The climate of the Upper Mississippi Valley is continental and cool. The nearby Mississippi River and its tributaries provide sloping lands that allows maximum exposure to the sun and for air to travel, keeping mildew at bay. Vineyards are planted in soils composed of mainly clay and silt loam on top of bedrock of limestone.
In the Upper Mississippi Valley River AVA, viticultural techniques must be adapted to deal with the cold winters. After harvest, many wineries will take the grapevines down from their trellises. The vines are then pruned and buried under mulch. In the spring, just prior to budding, the vines are then guided back into the trellises to begin the next growing cycle However, with new hybrid varietals developed by the University of Minnesota, these newer vines may stay on the trellises during the cold winters and pruned in February and March.
Grape varieties 
The Upper Mississippi River Valley grows mainly hybrid grape varieties like Chardonel, Edelweiss, La Crosse, Marechal Foch, Frontenac, Marquette, and Saint Croix. Research at the University of Minnesota, influenced by the work of horticulturalist Elmer Swenson, have been developing new hybrid grapes that could better withstand the cold winter and ripen earlier.
- Alcohol and Tobacco Tax and Trade Bureau - Establishment of the Upper Mississippi River Valley Viticultural Area 29395–29401 (E9–14574) Accessed: July 7th, 2009
- S. Hunt "Newest American wine appellation, world's largest" Wine Examiner, July 6th 2009
- P. Eyden "Making New Wine in an Old River Valley" Big River Magazine, September–October 2005