The success of California’s grape industry stands, in part, on the shoulders of its southern relatives. Native to the southeastern United States, muscadines and scuppernongs (Vitis rotundifolia) have superior disease and insect resistance compared to other grape species. In the 1930s, Dr. Harold P. Olmo, the University of California’s pioneering plant geneticist, thwarted attacks from grape pests by grafting California-grown European grape vines onto southern muscadine rootstock.
European grapes, also called bunch or table grapes, thrive in California vineyards. Although muscadine grapes can also be grown in California, they do not perform to their potential there, according to the California Rare Fruit Growers organization. Muscadines prosper in hot and humid climates of their native southeastern states. Fruits form loose clusters, in which grapes ripen individually instead of all at once as bunch grapes do. Their colors vary, including shades of green, bronze, red and purplish black. Named for the Scuppernong River in North Carolina, the scuppernong grape is a bronze muscadine cultivar.
Health Benefits and Uses
The National Center for Biotechnology Information reports that resveratrol contains many antioxidant and anti-inflammatory benefits that may lower cholesterol levels and reduce the risk of heart disease. This naturally-occurring plant compound is found in all grapes, but it is more highly concentrated in muscadines. Two ounces of muscadine grape juice contain as much resveratrol as 4 ounces of red wine. Powdered muscadine puree offers more dietary fiber than oat bran. Culinary uses include preserves, jellies, dumplings and bread.
The California Rare Fruit Growers website notes that muscadines are optimally grown in U.S. Department of Agriculture plant hardiness zone 7 and warmer. Successful cultivation requires climates with long, hot summers and lengthy growing seasons to produce good fruit set. Adjusting soil pH to a range between 5.5 and 6.5 and ensuring soil does not become waterlogged are required for healthy growth. Sites should provide at least six hours of sun each day. Muscadine vines are tolerant of drought, but during the first two years of establishment, plants should receive supplemental irrigation during insufficient rainfall. Based on soil-test results, local extension offices can advise gardeners on a fertilization regimen.
In 2002, nearly seventy years after Olmo's initial research, the U.S. Department of Agriculture's Grape Genetics Unit data supported his muscadine rootstock grafting procedure to breed exceptionally disease-resistant plants. Because of muscadine’s high disease and insect resistance, North Carolina State University notes that using insecticides and fungicides may not be needed. Applying a 2- to 3-inch layer of a non-nitrogen-releasing bark mulch in a 2-foot diameter around plants suppresses weeds, conserves moisture and reduces splashback of soilborne pathogens onto vines.
- The University of Georgia College of Agricultural and Environmental Sciences: Muscadine Breeding -- Past, Present and Future
- University of California Davis: Major Figures In the History of Plant Breeding at UC Davis -- Harold P. Olmo
- California Rare Fruit Growers: Muscadine Grape
- National Center for Biotechnology Information: Resveratrol as an Antioxidant and Pro-Oxidant Agent -- Mechanisms and Clinical Implications
- United States Department of Agriculture Agricultural Research Service: Food and Nutrition Research Briefs
- United States Department of Agriculture: ARS Research in Grape Rootstock Breeding and Genetics
- North Carolina State University: Muscadine Grapes in the Home Garden
- Muscadine Medicine; Diane K. Hartle, Phillip Greenspan, James L. Hargrove
- Creatas Images/Creatas/Getty Images