Black Rot Control in Grapes

DISEASE DIGEST

Now is time to get ready for black rot control in grapes.  A good fungicide spray program is extremely important for black rot control.  Good timing and right fungicide are all critical.  Early season control must be emphasized.  The most critical period to control black rot with fungicides is during the period from early bloom through 3-4 weeks after bloom.  Captan, a common fungicide, is only slightly effective against black rot.  Mancozeb, on the other hand, is highly effective.  However, mancozeb is not widely available.  Backyard fruit producers may need to ask a garden center or a retailer to special order mancozeb.  Another excellent product is myclobutanil (e.g. Immunox) which more readily available in many retail outlets.  For the most current spray recommendations, commercial growers are referred to OSUE Bulletin 506-B2, "Midwest Commercial Small Fruit and Grape Spray Guide," and backyard growers are referred to OSUE Bulletin 780, "Controlling Diseases and Insects in Home Fruit Plantings."