One should mark where the perennials are. Trust me!
I leave the stalks come fall/winter on some. Have the plastic tag with others. Some just have a plastic picnic knife at the spot. And then there are some What the H... is there!
So I am cleaning out a couple of 4 x 8 beds of that green weedy stuff and finding the new growth of my good stuff. Then What is that?
Another reason to mark is so you don't over plant. I had a couple of Astilbe. They were slow late fall, perhaps not seen. Then moved some bulbs (tubers?) of Bloodroot to a seemingly good shady area. Late fall got an orphan fern. Plunked it in. Bingo! Spring and new growth comes. Bloodroot made it through, fern can be moved, and astilbe on the safe side.
Good thing is seeing the new growth on all those plants!