Roses bloom like crazy in June, then when the heat gets intense in July, they rest. This is the time to fertilize your roses. Wait until the BIG bloom is over, deadhead the roses, trim back stems (not more than one third of their length) then add some fertilizer to get them through the stressful summer and to help them to produce more flowers. I prefer to use an organic fertilizer and I add some aged compost to the rose bed to cool the soil and preserve moisture.
Because I do not want to hurt bees, I do NOT use a systemic pesticide of any kind. When I see shiny leaves on the roses (that is the "honey-dew" from the aphid- translate: aphid POOP), I mix up a soap spray to control them.
Here is the recipe:
1 to 2 teaspoons of SOAP (castille soap, Dr. Bronner's liquid soap, Ivory soap flakes, or Dreft)
1 tablespoon of rubbing alcohol
1 quart of water
Add to a spray bottle and shake. Then spray onto the bugs. The spray has to touch the bug to be effective. Look on new stems, under leaves for the pests. It is best to spray on a cloudy day, not on a hot day, since the soap mixture could burn the leaves. I usually wait until early evening to spray, it's easy to find the sucking insects then and I don't have to worry about sun burn. Then, in the morning, if I sprayed the plant heavily, I will go out and wash the plant down with the hose. This is not necessary unless you have really doused the leaves top sides.
This mixture will kill off mites, whiteflies, aphids, thrips small scales and leafhoppers. This recipe has a very low toxicity to wildlife and humans.