Retaining wall - base layer

I had left enough space around the builders foam to add a retaining wall. I think the retaining wall is a nice way to finish the edges since I built up the land in order to have the leaf deck.

Since the foam layers are uneven, I cut strips of foam core board to act as filler and an even surface for the wood boards that will make up the retaining wall. Before gluing the foam core board in place, I added shims in a couple of places where needed to make the walls level. It already looks cleaner.