Apple powdery mildew

Asked June 17, 2013, 11:59 AM EDT

I have 4 apple trees in my back yard. To control this disease, I spray dusting wettable sulfur at the rate of 4 TBS p/gal,with a 5 gal battery operated sprayer. No matter how much I shake the sprayer while spraying,it is not enough to keep sediment from collecting in the bottom of the tank. The sediment plugs up the pump causing it to lose prime, and it won't work when I start on the next tank full. Its difficult to regain the prime. Is there a way to use this product to prevent plugging the pump? I know there are other effective fungicides, but is there any affordable for only 4 trees?

Genesee County Michigan apples apple diseases

3 Responses

Yes Sulfur is a big problem.
There is another material you can try.
Immunox by Spectracide.
Be sure you use the right formulation since Spectracide market several different materials and mixes under the same Immunox name.
Spectracide Immunox Multi-Purpose Fungicide Spray Concentrate

Thank you for your 6/19 answer on my sulfur spray problem for powdery mildew on apple trees. Over the weekend I was looking over Bulletin E-1723, revised march 1985, Cooperative Extension Service, MSU on backyard fruit sprays for insects and diseases and found a section on powdery mildew. It says Benomyl is effective against the mildew. Is this still recommended as an option if the product is still available?

Benomyl was removed by the manufacturer several years ago.
That class of fungicide was effective but the fungi developed resistance rather quickly.