Once the stems look dry and less fleshy, cut them off and discard,
clean the remaining tuber and store (stem side up) in a shallow tray filled
with dry peat moss in a cool dark place - basement, garage, etc.

Is the idea to envelope the tuber completely in peat moss, or set the
tuber in a shallow layer of peat moss that will soak up any moisture?

I'm guessing this same technique works for dahlia tubers.

-F