Rose bushes may become infected with bugs, such as aphids. While you can buy insecticides at a nursery or garden section of a hardware store, you can also make your own. Use a combination of water and dish soap to kill the insects. The dish soap breaks down the bug's outer layer, which renders it helpless.
Measure 1 tbsp. of liquid dish soap into 1/2 gallon of warm water.
Mix the soap and water mixture by swirling the bucket.
Fill an empty spray bottle with the mixture.
Spray on affected rose bushes, coating leaves, flowers and buds thoroughly. Spray in the early morning or evening to avoid burning the wet foliage in direct sunlight.