Powdery Mildew?

sparkles2307

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OK, all summer we havent had much in the way of disease or pests in our garden. Till yesterday. See, about 3 days ago there was a MASSIVE, 2-day long thunderstorm, we got like 3 inches of rain. NOW I noticed that my gourds have white powdery looking stuff on some of the leaves, is it because we got too much rain and they molded or is it PM? Would rain cause PM?
 

bid

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I would say that it is the humidity rather than the rain even though the humidity could be said to be caused by all the rain. The high humidity coupled with cooler night time temperatures and warm days and literally overnight you have powdery mildew.
 

sparkles2307

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so what do I do about it? The vines are already dying down for the fall anyways and we are scheduled for our first frost within the next 7 days...can I let it go?
 

bid

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Frost in a week!? wow! You can spray with milk/water or water/baking soda mixes...commercial sprays available as well. To kill powdery mildew all that is required is to change the ph a slight amount as the fungi grows in a rather narrow ph range.

Considering your season is winding down I would probably let it go myself. You can try disposing/burning of the plants rather than composting them to help eliminate the spores from overwintering after you pick your gourds. It will help some though not a lot really. Powdery mildew is just something we all have to deal with as the season winds down...and other times too sometimes. :)
 

digitS'

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bid said:
Frost in a week!? wow! You can spray with milk/water or water/baking soda mixes...commercial sprays available as well. To kill powdery mildew all that is required is to change the ph a slight amount as the fungi grows in a rather narrow ph range.

. . .
Narrow pH range, eh? Well, that would certainly make the mildew more controllable. I've never sprayed for mildew in the veggie garden.

In the ornamentals, where it's not just mildew but black spot and rust and where I'm not bringing in the product to eat . . . I've thrown the commercial stuff at it.

Zucchini seems especially vulnerable to mildew in my vegetable garden. I think you've got the right advice Sparkles but I want to add that months of exposure to the elements weakens the plants. I plant zucchini twice each season - late May and early July.

The May plants have almost run their course, right now. Meanwhile, the younger July plants are at full throttle. I've had to pull May zucchini by September because they've been so damaged by mildew. Not this year, but it hardly matters.

Steve
 

sparkles2307

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I will just let it go. Thanks for the tips. Our garden gets a healthy dose of our Angus herd's manure in the fall and spring, so we dont compost we just rip out the plants and feed them to the chickens and ducks. Glad its not the end of the world :)
 

bills

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My Zucchinis really got hit with powdery mildew, from just a few cooler nights, and heavy dews. I cut all the leaves back that were affected, down to the base of the leaf stalk. They looked pretty denuded..:( The smaller leaves close to the fruit, have since started to grow clear of the mildew, and I have gotten a bit more fruit off the plants. The blossoms have pretty well ended, so I don't expect much more now, but I did get a few more weeks life out of the plants..food for thought.
 

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