By Andi Anderson
A wet growing season across Indiana has created several challenges for pumpkin producers, especially after heavy rainfall affected many areas during August. Field conditions varied significantly, showing how important field selection and drainage are for successful pumpkin production.
One of the most serious problems observed was Phytophthora blight, a disease that caused vine death and fruit rot in fields that remained flooded for extended periods. In affected areas, growers are encouraged to remove infected plants and fruit to help reduce disease spread. However, successful management requires a combination of practices because no single treatment can fully control the disease.
As Dr. Dan Egel explained, "Management of Phytophthora blight with fungicides is not possible unless cultural methods are also implemented. Even the best management schemes, chemical and cultural, may fail to control Phytophthora blight completely when weather conditions are conducive to the disease."
In several fields, pumpkin fruit survived but vines rapidly deteriorated after prolonged soil saturation. Excess water can damage roots by reducing oxygen levels in the soil, limiting the plant’s ability to support fruit development. Growers must carefully decide whether to harvest pumpkins early or leave them in the field. While some fruit may not be fully mature, curing under warm, ventilated conditions can help harden pumpkin rinds and improve quality.
Another major concern this season has been bacterial spot, caused by Xanthomonas cucurbitae. The disease was found in multiple fields, even where copper-based products had been applied. Copper sprays act as protective tools rather than cures, and their effectiveness can be reduced by repeated rainfall, rapid plant growth, and incomplete coverage.
Dr. Mohammad Babadoost, University of Illinois researcher, has highlighted the importance of early disease prevention. Research shows that management efforts are most successful before disease levels become severe. Differences in disease severity were also observed among pumpkin cultivars, suggesting that growers should monitor varieties closely and select those showing better field performance.
Another disease found in several locations was Plectosporium blight, which can sometimes be mistaken for bacterial spot because of similar fruit symptoms.
Premature yellowing of leaves was also common in wet fields. Factors such as root injury, nutrient loss, powdery mildew, and cucurbit yellow vine disease contributed to plant decline. Growers are also being advised to monitor squash bug populations because they are linked to cucurbit yellow vine disease.
Overall, this challenging season highlights the importance of drainage, disease monitoring, timely treatments, cultivar selection, and careful harvest decisions. Lessons learned from this year’s conditions can help growers improve crop management and prepare for future growing seasons.
Photo Credit: gettyImages-digitalvision
Categories: Indiana, Crops, Fruits and Vegetables