Spring sure wish this container was much larger, I love your suggestion, but this is only 13" long x 6" wide and 5" deep.
By tough I mean it needs to be able to handle neglect, not being tended to on a regular basis.
Greg what was the name of that new sedum of yours, the brilliant chartreuse one?
What about a small clump of Armeria maritima Red Leaf, with a chartreuse sedum.