The recent development of Vitisriparia hybrids has allowed the expansion of the wine industry into Iowa and the Upper Midwest. These cultivars are more cold hardy and vigorous than traditional V. vinifera hybrids. During maturation the fruit tend to retain high levels of acids, exhibit a rapid rise in pH, accumulate high potassium levels, and possess a different profile of malic to tartaric acid than other hybrids. Wines from these grapes often have a “grassy” or “herbaceous” flavor. These same characteristics have been associated with fruit grown in shaded canopies. This study was undertaken as part of the USDA Northern Grapes Specialty Crops Research Initiative (SCRI) project to assess the effectiveness and cost benefit of various combinations of canopy management practices on improving the fruit quality characteristics of Frontenac, La Crescent, and Marquette wine grapes. This report summarizes part of the first year results.
Iowa State University
Rolfes, Dylan P.; Nonnecke, Gail R.; and Domoto, Paul A., "Canopy Management Practices and Light Interception of Northern Grape Cultivars" (2013). Iowa State Research Farm Progress Reports. 1916.