Photo by KCII’s Sally Hart.

Pink, white, yellow and red are just a few of the colors of roses in bloom in the area. Iowa State University Extension and Outreach horticulturists have shared advice on how to keep roses healthy and protected from diseases. Some rose plants may have round holes in their foliage, this is likely from leafcutting bees. Leafcutting bees are beneficial pollinators and damage to plants is usually minor.

Also, small, green worms may be seen on rose plants; these are probably the larvae of the rose sawfly. These insects feed on the undersides of rose leaves and can be picked off by hand and destroyed or controlled with insecticides.

Blackspot fungus is also common among roses. It is a fungal disease that causes circular, black spots on leaves, which will then turn yellow and drop prematurely. Fungicide treatments can be used to control blackspot. Also, when purchasing roses, select cultivars that are resistant to blackspot and plant in a site with full sun with good air movement to prevent it. Cleaning up leaf debris in the fall will also help reduce the overwintering fungi.