Squash Diseases

Squash diseases can happen anywhere. This page provides written and visual instructions for dealing and preventing plant diseases. There are so many types of squash and they do make a great vegetable anytime of year.

For the spring season I have had an issue with powdery mildew. I want you to know I was not paying attention as I should have. so by the time I caught it, it was too late to save my squash plants. I had to pull up the plants and destroy them. Make sure that you do not mix them in your compost if you have one. You do not want to ruin anymore of your crops

I made a second planting and noticed the same thing happening. I sprayed the plants with a liquid copper fungicide. It seems to be working.

We have had a lot of high humidity days, more rain than we have had in a while and many cloudy days which have made conditions ripe for powdery mildew. Yes, it likes lots of rain and wet conditions.

Below are pictures of my squash with the powdery mildew. In the first two photos, you can see the horrible white mildew on the squash leaves. These plants were too far gone so they were pulled up and thrown away.

Then I planted again and as soon as I noticed the powdery mildew on the squash leaves, I sprayed and it went away! In the third photo, the squash plant looks great after spraying with liquid copper.

Powdery mildew on one of my squash plants.
Powdery mildew on one of my squash plants. It started going away after spraying it with liquid copper.
Healthy squash plant after liquid copper took away the powdery mildew that was growing on it in my garden.

If you are getting a lot of rain, make sure you check on your plants often. If you see signs of disease, spray your plants with liquid copper. By spraying before diseases show up, you can prevent them. Spraying your squash prevents fungal spores, black rot, leaf spots, anthracnose, downy and powdery mildew, and early and late blight.

More on Squash Diseases

The best thing is to try to plant varieties that have built in resistance to diseases.  Hybrids usually have the best disease resistance.

Another technique is to use grafting.  This allows us to graft regular plants to a root stock that is full of disease resistance.  Here in 2014, I have acquired seeds and I am experimenting with grafting for squash.  This is new for home gardeners but some countries have been doing it for years.

More on Squash:

Growing Acorn Squash

Growing Winter Squash

Yellow Crookneck Squash

Return from Squash Diseases to Growing Summer Squash

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