In concrete jungles overcrowded by buildings, it seems no longer possible to add any green cover to the city. However, if you look at green cities from around the world, you’d find out that that’s not completely true. A slightly more expensive but space-saving alternative is still available. Why not simply plant the greenery on the wall? Simple isn’t it? Well, not quite, but Canada’s NSCC’s exterior living wall and many other locations around the world it is gaining a bit of success. A sister to the terrace and vertical gardens, if this concept becomes mainstream, then it might help in bringing down the rising city temperatures.