Salvia nemorosa (woodland sage) is a problem free & easily grown perennial that flowers for a long time, forming a nice, full, clump. The flowers cluster on purplish blue spikes on the long, strangely square shaped & fuzzy stems. The spikey leaves have a fine toothed edge.A very decorative plant, it is very attractive to butterflies too. It will bloom a 2nd time if you prune the first flower stems hard back immediately after flowering. Woodland sage mixes well with other perennials & is basically unmissable in your garden!