East Michigan vegetable update
Zucchini and cucumbers grown under low tunnels and hoop houses are being harvested. Field-planted crops are still going in.
Pumpkins are still going in.
Southeast Michigan vegetable update
Cucumber and melon growers should note that downy mildew spores have been picked up in spore traps on the west side of the state. None have been picked up by the traps on the eastside of the state, which are in the Saginaw, Michigan, area. Typically, we find our first downy mildew infected plants in Michigan around the Fourth of July.
Pumpkins have up to five leaves. Pumpkin, squash and zucchini growers should note that Enviroweather models suggest squash vine borer adults will start to emerge and lay eggs across our area in the next week.
Southwest Michigan vegetable update
Striped cucumber beetles continue to be active in vine crops. Continue monitoring and control as needed. Harvest from low-tunnel grown cucumbers, yellow squash and zucchini will begin later this week. We have detected downy mildew spores in our trap at the Southwest Michigan Research and Extension Center but have not observed any field symptoms. Protective sprays may not be warranted at this time, but scout and apply protection at the first sign of infection. Current hot, dry weather conditions are not conducive for spread, as the disease prefers cool, cloudy, wet weather.
West central Michigan vegetable update
Cucurbit downy mildew spores were detected at the Muskegon and Berrien County spore traps. The disease has not been detected in field plantings. Pickle, cucumber and melon growers should prepare to initiate fungicide programs earlier than last year. Check out Mary Hausbeck’s website to track spore counts and get spray recommendations for 2020.
Continue to be on the lookout for striped cucumber beetle, which seems to be a more persistent pest this year.
Squash vine borer eggs are small (1/20th of an inch), brown, flat and laid individually on the base of vine crops. Photo by Aaron Cato, University of Arkansas.
