When to Apply Epsom Salt Around Scuppernong Vines

To prevent a magnesium deficiency in your scuppernong vines, examine their lower leaves frequently for signs of chlorosis.


The term scuppernong can apply either to one particular cultivar of muscadine grape, Vitis rotundifolia “Scuppernong,” or to all bronze varieties of muscadine. Named for the Scuppernong River in North Carolina, they are descended from wild grapes and thrive in U.S. Department of Agriculture plant hardiness zones 6 to 10. Although pest and disease resistant, the vines frequently suffer from a magnesium deficiency. You can prevent that problem from scuppering your scuppernongs with an application of Epsom salt, which is actually magnesium sulfate.

Sampling a Scuppernong

Seedy grapes with thick skins and a musky flavor, scuppernongs are popular for eating, wine-making, and jams and jellies. They form smaller and looser clusters than the long and thickly packed pods of most table grapes, and the vines can scramble to 100 feet. Although scuppernongs will grow in western coastal areas as well as in their native southeast, the fruits produced in the west may be smaller and less sweet due to lower summer temperatures there.

Preparing a Place

Scuppernongs prefer a light, sandy, acidic soil with a pH between 5.5 and 6.5. If you have applied the dolomitic type of limestone to raise the pH, you probably won’t need Epsom salt, since dolomitic limestone includes magnesium as well as calcium. Make sure that soil is well-drained. Even though scuppernongs are common in coastal areas, they won’t tolerate standing water.

Diagnosing a Deficiency

Usually a magnesium deficiency shows up in the lowest and oldest leaves on the vine first, being indicated by a yellowing between the green veins on those leaves, known as chlorosis. This may begin as disconnected yellow patches and spread to cover entire leaves except for their veins and possibly their perimeters. Eventually the yellow sections will turn brown, causing the affected leaves to curl and die. If the deficiency becomes severe enough, it can spread to the newer growth, compelling the vines to drop their fruit early.

Applying an Antidote

For a 1-year-old vine, scatter 2 ounces of Epsom salts in a 3- to 6-foot area around the plant in July. Use 4 ounces over the same amount of ground for a 2-year-old vine or 6 ounces for a vine 3 or more years old. You should then water the area well to wash the salts into the soil. Alternatively, you can dissolve 1 tablespoon of Epsom salts in a gallon of water, and spray the vine with that solution every two weeks for the rest of the growing season.

About the Author

Audrey Stallsmith


Photo Credits

  • Stockbyte/Stockbyte/Getty Images
bibliography-icon icon for annotation tool Cite this Article