The wall starts as foam board 1" thick. I laid it down and placed the pots around where I wanted them, then used the pond variety of Great Stuff to sort of cement the pots into place. When the first layer had dried/expanded enough I put down a second layer that makes a kind of basket enclosing the pot. I think I did 3 passes with the foam, giving each layer just enough time to expand before doing the next, forming the basket shape around the pot and onto the board surface. The spray foam sticks very well to both the styrofoam and the plastic pot so the bond is strong enough to hold up the plants.
The next step was to pour/brush a non-toxic but water resistant wood glue and sift/drop handfuls of peat moss onto the glue.
The final step was to airbrush in some color with acrylic paint, to get some accent happening.
I hit the post button before I was done. I wanted to say, I made the cracks by standing the board up for a few moments while the glue was tacky but still fluid enough to drift down toward the ground. The cracks were then airbrushed.
If you look you can see small squares of plywood in each corner. Those are like washers, onto which I glued a stainless steel washer. Each corner is like that so I can bolt this, the interior wall, to the exterior, structural wall.
