Get rid of black spot fungus on flowers?

First, remove leaves affected and place in garbage. Do not drop on ground within 30 feet of sick plant. To prevent reinfection, make a solution of 1 1/2 tsp mild dish detergent and 1 g/2 gallon of water, mist lightly over entire plants. Also to prevent, water plants in the morning instead of late afternoon or night. Hope this helps.