I am rebuilding my 36" stone block wall that was pushed over this winter. I am currently excavating, and worried about erosion. Is there some thing I can do to help with that? I have heard of a material called Geo Grid, but cannot find a supply. What does this do? Do I need it, or is there another solution?
You'll need a proper base to set the wall on. You'll need a drainage space behind the wall to prevent water buildup. You'll need a landscape barrier to separate the dirt from the drainage material behind the wall.
Try searching, "retaining walls" and get a basic idea what's needed. Then go to the local masonary supply where you'll buy the materials and get their imput based on their experience with the local soil conditions.