A Gardeners Forum Forums General Discussion The Food Garden Forum Squash pest

I accidentally ended up growing a bunch of squash--I think they're all white bush scallop--in planters on my deck. They've been growing well; I've fertilized them a few times and I have to water them daily. But now they have these powdery looking spots, like mildew, on all the leaves. They're starting to produce a bunch, but I'm afraid whatever it is will kill my whole crop, because the leaves are starting to look yellow. Any advice? Is any of this due to nutrient deficiency? I didn't mean to grow them in such a small amount of soil, but once I realized what was growing it was too late to transplant.

I'd post pics but it looks like I need a website to host them on, and I don't have that goin' on.

By the way, I only use organic gardening methods. Thanks again for reading.

My guess is powdery mildew. Do a google image search and see if this is what your squash look like. It is what mine look like-- so I'm also searching for remedies. Mildew is a fungus so a fungicide should work. I've only come across one "organic" / home made fungicide: a mixture of water & baking soda. I don't know if it will be effective on powdery mildew.

If you water daily, and the pots are large enough (i.e., they don't really dry out completely every day) you may be over watering and may have created conditions favorable to fungi. Fairly deep, not over crowded pots shouldn't need to be water every day unless circumstances are extreme.

Good luck!

There are lots of organic fungicides that work well. I have used Soap Shield and other products from Gardens Alive. The best thing to do is prevent it though. Squash are one of the veggies susceptible to fungus so always water in AM or with soaker hose so the leaves stay dry. Don't plant them too close together. Keep the area tidy and remove yucky leaves right away and definitely do an organic fungicide spray about once a week this time of year. I have a bit of powdery mildew on the plants getting hit by the sprinkler but no fungus on those that are just soaked with a soaker hose. So you can see why those suggestions work. :wink: