Hi Lauriebasler and
Nice to see another PNWer!! I don't cover mine - I grow sempervivum and cover those, but the sedum I just let them do their thing. I do amend the soil that I plant them into, I use pumice (not vermiculite as that is so light weight it rises to the top - pumice is heavier and stays mixed in) so I use about 30% pumice when preparing the sedum bed or when it is in a flower pot/box
Hope that helps - also Springcolor gave me the idea to cut back the taller types in spring so they are a bit shorter - I don't cut them all, just the outer ones so the inner branches can be supported by the outer ones.
Cheers