The soil should be physically checked for moisture. Generally, in most areas of Colorado, the soil around roses needs a thorough soaking at least once a week. Newly planted roses may need more water than established plants because of the loose condition of the soil. Do not allow the soil around roses to dry out during dry, snow-free winters. Supplemental watering is needed during dry winter periods and monthly applications may be necessary.
Mulches help reduce moisture loss from the soil.
More recently, the rose midge and rose stem sawfly became problems in some areas. Verticillium wilt is also known to be a problem on roses in Colorado. In addition to the above pests, Eastern Colorado has some problems with blackspot, anthracnose and rust. Insects An application of a recommended insecticide starting when aphids first appear gives excellent control. A systemic insecticide also helps control thrips and the rose stem sawfly.