I've seen this type of "planting" in a number of different places.. (can't remember where I got
this picture) Anyway,,,,, everyone has a cement block, or two.

The Garden Junkie has lots of different hen-and-chick varieties and cute succulents.
Come out and see..

My cement block garden will be a "work-in-progress" most of the summer... as time
permits and as I get my cement blocks all painted before placing and planting.

See you soon.