QuestionHi..I am just sick ! !I have 24 red knockout roses and every one now has blackspot and are dropping leaves..Am I going to lose all of these roses ? ? Do I need to cut them way back now or just watch them die ? I have already sprayed with Immunox but it does not seem to help..I live in North Carolina and our summer has been an oven! ! Thanks for some suggestions in advance..
AnswerAll roses will go into a semi dormant state when the weather gets hot as roses hate high heat and will alway re-act to it by shutting down. High heat puts roses under stress and makes them vulnerable to disease and that is why you have got black spot. It really isn't a wisdom to spray anything on roses when the temperatures are above 80' not even fertilizers. Many times it will make the rose drop it's leaves. All one can do it wait out the heat and when temperatures return to normal, the roses then will start to grow normally. Wait until then to use your spray again for black spot. I too am having a heat wave in the PNW and the garden has never looked poorer. Usually I don't get black spot but because of the high heat, many of the roses have it. All flowers are drooping like they need water but they don't and many of the leaves are dropping. All I can do it hope that no one wants to view the garden!!