The vertical walls based on hydroponics are fundamentally unsustainable.They rely on constant monitoring by humans, they are artificial lige supporting systems unless they are fully emulating conditions that exist in nature which is rare. Unless a system is developed that invites spontaneous colonisation by plants – like porous sponge ceramics or concrete for example.Patric Blanc’s walls are more shopping centre or exclusive hotel gimmicks.
Recently proclaimed as “The highest wall in the world” on one tall residential building in Sydney almost totally collapsed and had to be reinstated at great cost.Paradise Project in London also collapsed with almost all plants obliterated.Green walls as amazing as they may appear allow only development of orchestrated ecologies reliant fully on ongoing inputs, maintenance and monitoring.
I experimented with various systems from eighties and have to say that vigorous climbers with the ground contact are far more superior to any synthetic medium.
Yes, there is a place for green gtricks but they are not panacea they are purported to be.