Planted Russian Sage over 6 years ago and have been able to trim it up in early spring so it shows itself as a small hedge row on the border of the planting bed. I find seedlings and move them to a opening between the "mother plants". That keeps the sage going from year to year. I like the flowers and fragrance of the leaves. I belive it helps keep some insects in check, or at least at bay. I have had blue salvia growing from year to year here in northern Indiana. I do give it some low level fertilizer in early spring. It is growing in a mulched area so is getting some humus from the mulch breaking down. The Sage family is one of my favorites.
The sage you mention is not a member of the Salvia genus. Russian sage is of the Perovskia genus (Perovskia atriplicifolia). However both Russian sage and Salvia officinalis, the herb used for seasoning, are members of the Lamiaceae family.
Both are lovely plants worthy of space in our gardens. I enjoy them both.