x
 
 
Learn which plants thrive in your Hardiness Zone with our new interactive map!

Grapevines & Leaf Curl

By Julie Christensen ; Updated September 21, 2017
Consult a county extension office to positively identify the problem.
Jupiterimages/Brand X Pictures/Getty Images

Grapevines produce large, succulent leaves that, when healthy, look beautiful in the home garden. Occasionally, the leaves may curl downward, an indication of disease, herbicide injury or a nutrient deficiency. Rarely, leaf curling may be a sign of drought stress. Keep plants healthy through good care so they are better able to withstand diseases and other problems.

Grape Leafroll Disease

Grape leafroll disease is more prevalent in vineyards than home plantings, but can have devastating effects, including the loss of 30 to 50 percent of yields. On red grape varieties, the leaves turn red. On white varieties, the leaves turn yellow. Both varieties exhibit cupping or downward turning of the leaves. The veins remain green. No chemical controls exist for leafroll disease, although treating aphids and scales through the use of pesticides may limit the spread of the disease. Plant certified disease-free plants and remove and destroy any infected plants.

Nutrient Deficiencies

Phosphorus and potassium soil deficiencies may mimic grape leafroll disease. Send a soil sample to a university extension office to evaluate the nutrient levels in the soil. Ask the extension office for fertilizer advice specific to grapes. Amending the soil with a balanced fertilizer may be all that's needed to resolve the issue.

Herbicide Damage

Glyphosate or phenoxy herbicides, such as 2,4-D, can cause leaf distortion and even plant death. The herbicides may drift from surrounding areas or may be applied by using a contaminated sprayer on the grapevines. Water the plants well to dilute the effects. Unless the damage is severe, plants usually rebound within a few months.

Considerations

Grapevines given proper care rarely suffer problems in a home garden. Plant them in full sun, allowing at least six to eight feet for each vine. Adequate air circulation keeps many diseases in check. Don't overfertilize the grapevines, which can cause weak, vulnerable stems. Remove dead or diseased foliage, stems and fruit promptly.

 

About the Author

 

Julie Christensen is a food writer, caterer, and mom-chef. She's the creator of MarmaladeMom.org, dedicated to family fun and delicious food, and released a book titled "More Than Pot Roast: Fast, Fresh Slow Cooker Recipes."