Answer: Unfortunately even the most disease resistant plants will not be disease proof/fully immune, and this is especially true if conditions are right for the problem to develop. (The northeastern part of the country is notorious for black spot.)Since Monrovia is a wholesale-only nursery, I can only suggest you consult directly with the nursery where you purchased them if you are dissatisfied with the plants. Also, your local county extension may be able to help you develop a control program for your plants. I am sorry this has happened to your roses.
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