Russian sage is actually perovskia atriplicifolia. Armitage says to propagate by "offshoots which occasionally arise after 2-3 years or take softwood curttings in the summer. Take a 3" long shoot, including stem and leaves, dip in root hormone, place in sand, and cover to maintain humidity...roots appear in 14-21 days."

In our garden, it is extremely drought tolerant and has set seedlings here and there but nothing obnoxious. My husband and I were admiring our city's skate park for kids, which is bunkered with ornamental grasses, russian sage and rose of sharon. Hope those little skater dudes appreciate it!