Zack Benson Photography I used a Concrete Block Adhesive to hold it together. I found it at Home Depot in the glue section. Hope that helps. To keep the dirt in I just used metal screens and block adhesive. Here is a photo of the underside of one of the blocks.
Custom Home Planning Center 36 full 2 1/2s
If not on a slab run 10" alm flashing under 1st course. If they clime it will station a cat or a child with a wooden mallet to "wack a Mole"
This is a great way to put those old, misc. cinder blocks to use. I used some to plant miniature roses, although I wasn't quite as creative with the design. However, you want to stick to plants that don't have extenstive root systems.