Use any type of ornamental grass, annual or perennial tolerant of full sun in front of a knockout shrub rose. Limit choices to plants up to 12 inches high at maturity to serve as a frame for the rose bush. Select hardy cultivars in USDA Hardiness Zones 4 to 9 to accommodate the same growing conditions as the knockout shrub rose.
About this Author
S.F. Heron is an avid gardener with three years of experience in online writing and a working background in aviation and earth and ocean sciences. She is published on various sites, including Helium, eHow and Xomba. She holds a Bachelor of Science degree in journalism from the University of Maryland.