What are some general treatments for blackspot?
A number of rose growers have expressed the opinion that the prevalence of blackspot in their gardens during the past year was greater than they had experienced in some years and wondered what the reason might be. There are probably a multiplicity of reasons depending on the specific garden, and I thought it might be of value to readers of this newsletter to comment on the practices which might be helpful in the coming year to control this omnipresent rose disease. In my experience, other than the Rugosas, R. rugosa and hybrids of that class of roses, there are few roses which can be termed completely resistant. Among the hybrid teas, floribunda and miniatures, the most prevalent classes of roses in our gardens today, there are not any varieties, in my judgment, that are completely blackspot resistant. They are all vulnerable, some more so than others. I used to tout Sun Flare, for example, as a blackspot resistant floribunda; however, it too is susceptible at times. The best we can ho
