Rose Black spot

Question

Can Moss cause leaf spot on ornamental shrubs? As I was cleaning around the base of my rose bushes, I noticed small patches of Moss. I’m wondering if this may have caused some of my Black Spot problems this year.

Answer 1

Moss will not cause blackspot as such, but will certainly harbour the fungal spores and should be removed. The best treatment is a fungicidr applied once or twice early in the season before the disease appears - also by now dispose of all the infected leaves.