This cultivar of unidentified parentage which was originated by Hajimi Sugita of Japan and registered on his behalf by Peter Ruh of Ohio in 2003. It has rich blue-green foliage that is moderately wavy and develops slight corrugation as the clump matures. A large plant about 23 inches high by 53 inches wide, 'Blaue Ruh' develops pale lavender flowers in July.

According to The Hostapedia by Mark Zilis (2009), "...an outstanding example of a fast-growing, blue-leaved cultivar."