Vertical farming doesn't have to be high-tech. This is the building going up opposite us. Simply having the wall of the veranda 1m further back would open up all such possibilies. We're going up to Haikou next week and I'll look for examples of how green the sides of the residential blocks can become.

This one is below my window, as evidence that people who live in this kind of building would utilize any space they had available.