Ask away mate, bottom line is as much as I am a big fan or urban greening in general for so many ecological reasons. I think in practice they are a nightmare on so many levels, Having a lot of experience i this field as a systems designer I do not thing the are practical. and one hole in that waterproof membrane either vertically as in green walls or horizontally as in green roofs Green roofs being the lesser evil of the two.
In reality we all know as normal building age buildings age things go wrong and damp is a big problem

I do not believe the hype any more. Look up french green wall designer Patrick Blanc I believe he is the leader in this field

The cost of this would be about (In Australian Dollars)
Installation: $1,000 – $2,500 per m²

At ~5 stories, say the wall is 15 m wide x 20 m high = 300 m²

That’s $300,000 – $750,000 AUD installation cost.

Ongoing maintenance: $100 – $200 per m² per year

Around $30,000 – $60,000 AUD annually for upkeep.

Lighting & irrigation system: included in the above, but can add $50k – $100k upfront depending on complexity.

Agreed beautiful study of how nature colonises species

Nice work mate, Scares the hell out of me though. All those years of learning how to render down the drain. Makes me a bit sad

Nice work I would not even attempt something like that