Chemical Warfare on Blackspot: Bayer Advanced All-in-One

This is the second year that my roses have suffered black spot. Not as bad as last year, but still bad.

 

I've tried the Ultrafine oil, the Rose Defense (Neem oil), baking soda and detergent, strong jet of water... none of it worked for me. So I invested $15 (Home Depot. $20 at Summer Winds, aka Woolworth's) in Bayer Advanced All-in-One. Poured it on in June. So, don't know the various interactions with the humidity, sun, etc. etc., but it does seem to work somewhat. I still see some leaves turning brown and falling off, but the plants are blooming well, putting out strong canes... This weekend is time for the second application so by late August, I will have two data points.