Mike, I think you're spot on. When I upended the container, only the top half spilled out. The whole bottom of the container was sodden - with a bunch of earthworms no less.
Base wasn't rotting, so I think I caught it in time if excess water was the culprit.
I just repotted into different potting soil w/ lots of perlite, set it up on a old mesh garden cart with a sisal rope thru a bottom hole that will wick away lingering water.
Thanks for your help. Hope Hetty agrees.
Monica