Jerry Brust, IPM Vegetable Specialist, University of Maryland; firstname.lastname@example.org
One of the main things a grower can do to ensure a good quality pumpkin is to be sure that they maintain their fungicide applications for as long as they continue to harvest fruit. Maintaining good foliage cover for your pumpkins results in pumpkin handles that are dark green, stout and firm (Fig. 1). If fungicides are cut too soon, foliage can be lost to powdery or downy mildews or other foliar diseases and this defoliation can result in handles that are brown, withered and decayed (Fig. 2).
Another reason to keep your foliage in good shape is that pumpkins that are maturing and turning color need to be protected from the sun. With our hotter and usually sunnier September weather pumpkin fruit can easily become sunburned or sunscalded. Areas on orange (or at times green) pumpkins that are facing the sun can become reddish or bleached white (Fig. 3). These sunburn/sunscald areas on the fruit often become soft, with rot setting in a few weeks later. Clear, sunny days with highs in the mid to upper 80s °F are perfect settings for sunburn/sunscald of fruit, especially if the fruit has been clipped and left in the field. I have seen several pumpkin fields (especially U-Pick ones) over the last 3-4 years that suffered significant losses to sunburn because of reduced leaf cover due to unchecked foliage diseases.
Figure 1. Harvested pumpkins with good handles
Figure 2. Harvested pumpkins with poor handles
Figure 3. Sunburn (red spot) and sunscald (white spot) on harvested pumpkins