The Michigan State University Vegetable Pathology Lab teams up with Michigan State Extension to publish vegetable updates throughout the growing season. View previous updates here.
Southeast Michigan vegetable update
Pumpkin plantings have some orange fruit, though some plantings still have a long way to go. This unevenness and lack of orange fruit is being reported across the state. Powdery mildew is quite developed in some fields, giving the plants an overall yellow appearance. The recent wet weather has spurred phytophthora development in some field with a history of the disease.
Spider mites are out and feeding in watermelon. This quickly reproducing pest is most often seen in fields that have experienced hot, dry conditions and repeated exposure to broad-spectrum insecticides. Spider mites can feed on a variety of crops, but they really gravitate to watermelon.
West central Michigan vegetable update
Cucurbit downy mildew has been detected in seven Michigan counties including Allegan, Muskegon and Kalamazoo. Cucumber, cantaloupe and watermelon growers need to apply downy mildew fungicides on a seven-day schedule.
Powdery mildew colonies continued to increase this week in two pumpkin fields
Phytophthora capsici continues to cause issues in cucurbits. Besides fungicides, a key management strategy is to disk under heavily infested areas along with a firewall of asymptomatic plants.