I'm making a raised garden bed that is about 2 cinder blocks high (with 1 extra cinder block below ground as footing) in a square shape 3.6 meter each side.
So far I made a footing of 5 cm of concrete, than laid a course of beam type cinder block (shaped like a U) with steel bar inside and filled with handmade concrete (this is below ground level). I already I laid the middle course of cinder block and now I must make the last course. I will probably finish the top with granite.
Now, the middle course should be solid filled with mortar or concrete? The top course should be made of regular cinder block or the U beam type? I have a lot of cinder block available so if possible I would like to use it instead of the beam type block.