Looking to get some input here. I am going to be installing a drystack wall and a couple of planters. The material is going to be 1- 1 1/2" New Mexico Buff flagstone. We had built a small wall for a customer using this material and they loved the thinness of that stone. The wall obviously had many layers which made it look less bulky almost waferlike and had rough front edges. I had watched some very large drystack commercial projects out here a few years ago where the walls up to about four feet high were drystacked with a slope behind them. The void behind the built walls were about 1 - 1 1/2 foot wide and loose concrete was poured in behind, tamped and filled almost to the top then backfilled after drying. You could not see the concrete. The walls looked amazing as there was no mortar work needed between the stones in front. This produced a very clean look. The capstone was dimension cut and mortared. I am assuming this loose concrete in back glued/cemented the whole thing together. That said those walls still look great today. Has anyone had experience with that sort of build and have any insight? Our project will have an average height of 2 feet and in some places almost 3 feet. The longest run is 80 ft.