Updated: February 20, 2023

      1. Spray damage (Phytotoxicity-Leaf burn) 

multiple spots on grape leaves from spray damage
Leaf burn

Sulfur, copper, and copper sulfate (Bordeaux mixture) fungicides can burn the foliage of certain grape varieties (Concord). Read the label of the product you intend to apply to determine the percentage of the active ingredient and any cautions that accompany its use. Do not use pesticides on stressed plants. 

     2. Drought/Environmental Damage

Caused by lack of moisture and hot, dry temperatures.