How to stop mildew on my Roses? Whatever I use it keeps coming back!

Have you tried vinegar?

copper fungicide

Try milk

The formula is 30% organic milk and 70% water; use a 10:1 ratio of water to milk and was found to be helpful at keeping powdery mildew at bay for roses as well.

Powdery Mildew Spray with Milk:

Several studies have shown that using milk or whey have been as effective as sulfur based mildicides.

It is very important that you wet both sides of the leaves AND you spray when it is sunny and hot. Spray around 2 PM in the afternoon.

It doesn’t matter if you use non-fat, whole, or skim milk.

It sounds like you need to move your roses. I'm faced with the same issue ... the bushes get too much water in late spring, then the extremely high humidity through summer (in Fla.), leads to the powdery mildew. Also do a soil drench with the fungicide if you use it. Elfrieda, I'm going to try milk this year!

I saved up all the ashes from the smokers in my home and asked my neighbors to do the same. What nicotine left in the ashes, kept black mold from forming on my roses, and any other little critters that think roses are meant for them. I not get comments all the time on how beautiful my roses are. The roses absorb the nicotine through the roots. This was so successful, that I also started to put the ashes throughout my whole flower garden. No more spraying, removing critters from the back of the leaves.

water roses from the bottom, not on foliage, morning is best. Try using an antifungual spray.