This sub section of the area 'exposed masonry' is about the greening of facades made of natural stone and quarry stone. Your weaknesses are illuminated, and with reference to examples shown. Many kit ranges from FassadenGrün are applicable.
Natural stone facades can consist of broken, barely worked stones (rubble stone) or of hewn, dimensionally stable stones or blocks. Depending on the stone type they can be very large, but also quite small block sizes are possible. The stones are always joined together by mortar, mortar joints can, especially with rubble masonry, be very broad with larger blocks of stone but also very narrow and unimpressive.
Natural stone facades may be a strongly weathered and already cracked and torn. They are then only partially suitable for wall mounts and must be plastered, so that now the wall is plaster masonry. Please always advise yourself of the sustainability of the stones, before installing a climbing aid.
Also overhanging components of a facade such as cornices, etc. can be made of natural stone such as soft sandstone. They are only suitable for fixing brackets at a certain thickness, also material strength, and in the case of doubt, it is always preferable to use spreading pressure-free anchoring, i.e. bonding with composite mortar.
With excessive unevenness in the masonry are wall mounts preferred to be used, which project outwards, in order to achieve a sufficiently large wall distance. If necessary, use more holders as planned, because at some point a mounting is not possible.
Basically all 5 FassadenGrün construction styles with the standard mounting brackets are suitable. It is fastened in the stone or in the joints, possibly both- stone AND joints, in order to maintain a selected grid. In critical filling (really only then) should no plastic and metal dowels be used, which unfold with a destructive expansion pressure on the rock, i.e., with narrow stone profiles as cornices, etc.. It is better then to use expansion free anchorage with composite mortar. Hammer drills, universal drills, and percussion drills are equally suitable.