stainlessbrown
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pretreatment for squash/mold/fungus

Anyone have suggestions for a preventative approach, rather than waiting for the powdery evidence that your plants are infected?


I thought about just starting very early with Neem oil, or maybe try the milk mixture, but as several of my plants already have small squash on them... does it matter?

anybody try7 mixing milk with the Neem oil?

California upper central valley

imafan26
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Actually prevention is better than cure. I don't have to spray all of the time only when certain conditions exist.

Before rain is expected I can use the neem or even horticultural oil will work as long as the days will not exceed 80 degrees.

Make sure you have good air circulation around your plants

If it rains for days. I need to spray within three days of the rain stopping. It is the humidity after the rain stops that promotes the growth of the fungal spores.

If the weather is hot and dry but not particularly humid, I do not need to spray.

I haven't tried to mix oil and water, so I don't know if it is any more help.

I would rather use sulfur instead of neem oil but it is next to impossible to find wettable sulfur and the ready made sprays are costly and don't do a very good job.

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applestar
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".. Does it matter?" ...what? Does it matter if you don't spray?

I typically start spraying with milk solution and alternate with AACT solution as most benign products that can be used as preventive for fungal diseases.

I don't use sprays that could potentially kill the beneficials, so I would not use neem oil or baking soda with soap and oil sticker. Sulfur might kill the beneficial predatorial mites.

There is controversy over what it is about the milk spray is the effective agent. One theory is that the milk helps to culture lactobacillus type bacteria on the phytosphere which out competes or even preys on the fungal spores. Some people say milk attracts mold that grows on milk and they are what out competes with the disease causing fungal spores, and some people say they create environment that is preventive. I have also read that it's the milk protein.

AACT (actively aerated compost tea) is seething with microorganisms, so it's easy to imagine that they would also out compete the fungal diseases or that they would prey on them. It also fortifies the plant's defenses. It makes them healthier which makes them less attractive to pests and diseases.

The two are not necessarily acting in concert so I would not mix them and use them together.

stainlessbrown
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well rain nor high humidity are much of a concern here as we're dealing with a drought, so perhaps the fugue/mold is different here (?)... typically a gray spotty/powdery appearance which causes the leaves to look...poorly

"does it matter" was referring to the fact that the squash plants have already set fruit (meaning, would spraying be good/detrimental/neutral) to them

AACT- what is your formula for this?

Thank you

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applestar
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Interesting question.

Two possible alternative suspects I can think of are russet mites if we were talking about TOMATOES --- do russet mites also attack cucurbits? ...and pickleworms.

I generally make AACT using the most basic recipe -- shovelful of home made compost, a dribble of unsulfured molasses, and almost 5 gal of rainwater or de-chlorinated water. 2000 or 3000 aquarium pump with 4"D disk stone now but used to use a coiled 1/4" soaker hose. Use between 16-30 hrs (I don't go crazy sticking to a set schedule).

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applestar
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imafan26
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I thought it was the acidity of the milk that inhibited fungal growth. I should try to research that again.
Sulfur was less damaging than neem. Sulfur could be used in summer where the heat contraindicates using summer oils. Summer is usually when I also have problems with spider mites and sulfur works on them, although they will also kill beneficial mites, they don't kill all beneficials or potentially harm bees. Summer oil would be best since it pretty much coats the leaves and repels water.

I tried cinnamon, but I did not go a good job of filtering it and it clogged my sprayer.

I also heard of using baking soda, horticultural oil an insecticidal soap, 1 tablespoon each in a gallon of water.

And AACT as a preventive. Although I still believe if plants are kept healthy, well fed, have good air circulation and sanitation is maintained by removing diseased plants and leaves fungal problems can be minimized.

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rainbowgardener
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It still sounds like you are describing powdery mildew:

Image
https://gardeningintunewithnature.bangor ... r-Leaf.jpg


as the disease progresses the leaves get yellowed and ragged, "looking poorly."

Unlike many, "Powdery mildew is a fungus that grows well in arid climates" https://www.colostate.edu/Depts/CoopExt/ ... mildew.htm

anything you do against powdery mildew works much better as prevention than cure.

There's a whole big thread on AACT (aerated compost tea) in the Compost Forum here.

And yes it matters, assuming you want your squash to keep producing after the fruit that are on it now. For me powdery mildew tends to show up later in the season, in summer, not in spring.

Another useful preventative measure is baking soda solution.

stainlessbrown
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It's the powdery mildew based on the photos- and you're correct it does show up later in the season, but I thought I'd change my mindset to preventive rather than reactive- I'll do some more research on the various methods suggested (now that I have various methods suggested)

Thanks everyone!



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