Thanks all for the replies, and thanks Anne for the welcome back (I've been too busy! need to update my bio - the pond is in, an off-grid cabin is in, too! And the place is STILL available to share!!!
https://hewittfarmspics.smugmug.com/Projects/The-CABIN)
ALSO thanks for the SIMPLE recipe, I DO have these ingredients on hand ... I'll give it a try.
A really good treatment for powdery mildew is: 1 gal water, 1 T dish soap, 1 T baking soda.
I put it in a spray bottle to make applying it easy.
Some recipes call for adding oil. I have never found a need for the oil.
NOW, HOW do I properly dispose of the plants I cut down? NOT going into the compost pile, so WHERE? Can I burn, or will that spread fungus, too? In black plastic bags? What a horrible single use of horrible plastic! Are there better options?