Who is doing it?

Mexico City is making good use of the pillars along its highways by turning them into vertical gardens, helping the busy city to breathe again. Thanks to a project called Via Verde, 1,000 highway pillars will be turned into vertical gardens. 

The pillars are covered in pockets of felt in which different kinds of plants are planted. These gardens have their own system for collecting rainwater, and even have sensors so that they can be monitored remotely.