New to the garden scene. I had a bunch of perennials planted last year for a Zen garden. After the treacherous winter we overcame, whatever leaves that remain on the plants are now either brown, covered with black spots, or just leafless stems. My question is, when pruning, do I cut off just the brown and black spotted leaves individually from their stem? Or do I cut the entire stem near the ground somewhere that holds all the leaves together? Some stems have healthy green leaves along with some brown and/or black spotted ones together. Also, the stems that are just laying on the ground with no leaves attached, do I cut them at all, or wait for some new leaves to begin blossoming? Thanks.