Grapes in the southern half of the state will soon be reaching the critical pre-bloom stage, which is a key time to control important diseases such as black rot, downy mildew, and powdery mildew. The next three or four sprays will be critical in controlling fruit infections. Growers should pay extra attention to getting thorough coverage and use the best fungicides available. The Midwest Fruit Pest Management Guide lists a wide range of products recommended. A protectant such as mancozeb or captan plus one of the sterol inhibitors such as Bayleton, Mettle, Procure, Rally or generic tebuconazole is the recommended fungicide treatment. Rotating with of one the strobilurins such as Abound, Sovran, Flint, or Pristine is a good option as well. The combination products such as Inspire Super, Revus Top, Quadris Top and Adamant should also be good for broad-spectrum disease control. Be sure to read the warnings about phytotoxicity with fungicides containing difenconazole. These next few sprays are critical to producing sound, clean fruit. Pay attention to detail now to assure excellent fruit quality at harvest.
Grape cluster at immediate pre-bloom stage
Grape cluster at early bloom