Crocs are already full of holes! I have so much planted in the top of them, I don't think the water pooling will be a problem. I'll probably just spray them occasionally. I did add a piece of plastic "onion bag" inside each shoe to hold the soil. And I 'pinned' the sedums with tiny copper wire so they wouldn't fall out when I hung it. A friend sent me a pic of crocs with flowers in them. I think those would be harder to keep watered than the succulents.
thanks goldfinch....I never owned Crocs, but I wish I had bought stock!