I'd like to do an above ground garden just for beans along my fence wall which is really my only place with full sun. It will be on top of river rock. Considering our 115 degree temps and the fact it will be along a west wall ( east side of my west wall), how wide and deep do I need it? I'm thinking pole beans on a trellis. Probably limas, butterbeans and yardlongs in the summer, standard heirlooms ( hoping to get tennesee cut shorts and some other shells, greasies) for cool season. Green peas for winter.