Dean A
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Joined: Mon Mar 20, 2017 5:17 am

Powdery mildew

Hi How do i get rid or eliminate powdery mildew?

Thank You guys

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Super Green Thumb
Posts: 25303
Joined: Sun Feb 15, 2009 11:04 pm
Location: TN/GA 7b

Re: Powdery mildew

Organic fungicides include diluted milk (any where from 10 to 50% milk, allow to sit until it is room temperature), hydrogen peroxide sprayed straight from the bottle (which is a 3% solution), baking powder solution (1 teaspoon baking soda to 1 quart of water, plus a few drops of liquid dish soap), Neem oil, etc.

You can't mix treatments, but you can rotate/ alternate them. They will need to be repeated every week or two or after it rains.

All of them work best as preventative or if you catch it very early on. If the disease has already progressed, remove the affected leaves first. Spray thoroughly including underside and top of leaves.
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Joined: Tue Jan 01, 2013 1:32 pm
Location: hawaii, zone 12a 587 ft elev.

Re: Powdery mildew

Powdery mildew is a problem in wet humid conditions. It will appear on susceptible plants within 3 days after the rain stops. So it is important to start spraying before if you know rain is coming and to spray immediately after the rain has stopped to keep the mildew from getting a foothold. You will need to continue treatment as long as the humid conditions exist. Improve air circulation. Tie up vines and trim off excess leaves. Make sure plants are spaced well. Remove all debris and infected leaves. If a plant is too far gone, remove it so it won't spread the spores to others. Fungal diseases are easier to prevent than to cure.
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