Silicate has been studied extensively in a variety of crops over the past 20 years or so, and has shown to have av positive effect in enhancing disease resistance in a wide range of genera. I used Dyna-gro’s Pro-teKt for a while 15 years ago, on roses and couldn’t say that i saw definitive evidence of improved Blackspot resistance. But I didnt do a control study, so there may have been some effect that i just wasn’t measuring.

Thanks for posting the article. I had tried Dyna-gro Protekt as well when I lived in Texas, but I tried so many different things simultaneously so I can’t say which ones prevented the disease. But I’d say Mancozeb and Propiconazole, more environmentally consequential chemicals ,gave the greatest protection. If I stopped beyond their recommended interval , blackspot would start to appear.