The most common rose pests are aphids, Japanese beetles, rose midge, cane borers, and thrips. Leaf-cutter bees cause slight cosmetic damage like small holes and skeletonized leaves, however these are important pollinators of other plants...so think twice before killing those. Dislodge the pests with a strong stream of water and spray the plant with insecticidal soap. You can also encourage predators of rose pests by planting geraniums or sunflowers nearby. Good luck!