https://journals.plos.org/sustainabilitytransformation/article?id=10.1371/journal.pstr.0000156
I checked out this article about green walls in tropical climates, and it turns out their orientation really affects how much energy a building uses! They tested a bunch of different plant species on walls facing different directions and found that east-facing walls were the real winners when it came to saving energy. So, if you're in a hot spot and looking to cool things down, an east-facing green wall might be just the ticket!