brown spots on my autumn joy sedum

by Amy
(Cumberland, WI)

I just planted 3 autumn joy sedums this year. I live in Zone 3-4 in Wisconsin. They have brown spots on the leaves & the leaves are falling off. What is this & what should I do.

Doug says that it sounds as if they're being overwatered. Dropping leaves means a root problem most of the time and my best guess is too much water on this full sunloving, drought tolerant plant.