I am brand new to making anything like this. I am making several short (height) retaining walls in my yard. I have cinder blocks for one area (8"x8"x16") and dry stack stone blocks trapezoidal shaped for other areas (6x7x17.5). In either case, I am only stacking them 2 pieces high. Both the cinder blocks and the stone blocks have holes in them.The goal is to make a rectangular raised garden bed with the cinderblocks and some other semi-circular shaped raised garden beds with the stone blocks.My question is regarding how I should lay and reinforce the cinderblocks and the stone blocks. I am planning on laying down about 2 inches of gravel underneath all areas where the blocks will be stacked and then placing the blocks. I am not sure if I should fill the holes of all blocks with gravel, and/or quikrete and/or rebar or what.I am in southern california where we dont get a ton of rain and hot dry summers.edit: typo via /r/DIY http://bit.ly/2LM1EGz
