Black spots on rose leaves

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Question by: Volkhardt B

Dear garden expert, in October/November, my rose leaves featured black patches, even though I had sprayed them in September. For private reasons, I had no time to spray them again. Because all the leaves fell off, my question is what should I do in spring – wait to see what happens, or spray the first leaves as a preventative solution? In addition, I have added bark mulch in particular around the stems to protect against frost. Should I remove this again in spring?

The GARDENA gardening expert

The black patches are black spot, a leaf fungi infestation which attacks roses. Basically, it is easiest to reduce infestation by planting more resistant varieties of rose.

However, dear Mr. B., because your roses are already planted, I would advise the following procedure: Remove any rose leaves remaining from last year from the entire rose bed. Spray the roses regularly against black spot. Alternate each time the active ingredient in the spray to prevent the parasite from becoming resistant. To do this, look at the declaration of the active ingredient on the product packaging, as the same active ingredient may be contained in preparations of different names on the market. When spraying, also spray the surrounding soil thoroughly, above all where spores are lying.