How to Prevent and Treat Powdery Mildew on Pumpkins

If you’re growing pumpkins in your garden, you may have seen white spots appearing on the leaves and vines.

What’s up with that? It’s likely that your plants are infected with a fungal disease called powdery mildew.

This disease is very common and in many cases can be treated successfully. However, if it is allowed to spread, in severe cases the plants may drop their leaves and expose the fruit to sunscald.

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In addition, the developing fruit may be stunted and fail to ripen properly.

Flower buds can also be infected which will prevent them from opening and they’ll dry and fall off the plant.

As Dr. Dan Egel stated in a Purdue University Vegetable Crops Hotline article on Pumpkin Disease Management Steps, it is “nearly impossible to find a pumpkin vine in August without powdery mildew.”

However, with a little proper planning and diligent care, this does not have to be the case!

Read on to learn how to prevent and treat powdery mildew on your pumpkin plants.

Here’s what I will cover:

Powdery mildew is a very common plant disease caused by hundreds of different species of fungi.

While the infection doesn’t typically kill mature pumpkin plants, it can cause problems in the developing fruit, and can cause stunted growth in young plants.

The name is derived from the typical symptoms that first appear as white spots on the leaves and develop into a grayish-white powdery substance covering the foliage.

This “mildew” consists of a combination of fungal spores and threads known as mycelia.

In pumpkins – and cucumbers, squash, melons, and ornamental