Pumpkins have become a major fall crop for many Michigan producers and planting time plays an important role in crop yields. In Michigan, the thought used to be that planting could be as late as June 25, primarily because this meant less time spent battling powdery mildew in September. With availability of new varieties and more effective control products, planting this late is more of a detriment than a benefit.
Planting in late June provides approximately 100 growing days (maybe less, depending on where you are growing), which limits the varieties you can choose from, among which are newer varieties with various of tolerance to powdery mildew. It used to be that powdery mildew, and the eventual leaf collapse, fruit damage and rot associated with this disease, was inevitable, but these tolerant varieties, as well as stronger fungicides, make controlling this disease more manageable.
