Muscadine Vine Life Expectancy

Adaptation

• Muscadine vines are indefatigable in the hot and humid climate of their native Southeast. Although muscadines grow in U.S. Department of Agriculture plant hardiness zones 7 and warmer, they flourish only in regions that have long, hot summers. Even if you live within these hardiness zones, muscadine vines may be short-lived or may fail to bear grapes if your summers are not sufficiently long and hot. For example, Oregon lies within USDA zone 8, which is within muscadine’s hardiness zone, but summers there are too cool to support healthy muscadine growth.

Disease Resistance

• Muscadine’s longevity is partly due to its ability to withstand most of the diseases that attack other grape species. Typically, muscadine has immunity against Pierce’s disease and phylloxera, both of which are devastating to other grapes. However, the humid climates where muscadine is adaptated may also promote fungal diseases. If you plant disease-resistant cultivars, such as “Black Fry,” “Jumbo,” “Supreme” and “Cowart,” you may increase the life expectancy of your vines by boosting their disease immunity.

Site Preparation

• Establishing healthy muscadine vines is a primary strategy for ensuring their longevity. Preparing the planting site is best accomplished a year before you plant the vines. Removing all weeds from the site will remove the plant competitors that vie for water and nutrients, which should be directed exclusively to the muscadine vine roots. Based on soil test results, dolomitic limestone should be tilled into the soil at least 8 inches deep, and optimally to 24 inches, to adjust the soil pH to 6.5.

Fertilization

• The first three years after planting muscadine vines are the most critical to ensure their longevity. During the first year, muscadines need three applications of fertilizer, each broadcast in a 2-foot area around the vines but no closer than 6 inches from the trunk. Make the first application at planting by applying 1 cup of 10-10-10 fertilizer, and make the second and third applications in late May and early July of 2 ounces of ammonium nitrate each. The second year, make three fertilizer applications at the same times you did the first year, but double the amounts and increase the application area to 4 feet. The third year, increase the application area to 6 feet, and broadcast 10-10-10 in the amounts of 2 pounds in March and 1 pound in May. After this three-year establishment period, maintain established vines by applying 3 to 5 pounds of 10-10-10 per vine each March and 1/2 pound of ammonium nitrate the first of June. Monitor the soil pH by testing every three years and adjust it to 6.5, if needed.