Hi Tracey, Thanks for your question, isn't the living wall gorgeous? According to the story, the wall "holds a lush assortment of herbs, geraniums and mosses. A watering system trickles down the wall to keep the fragrant bursts of mint and lavender fresh." I encourage you to reach out to the designer behind this space, Siol ( http://www.houzz.com/pro/siolstudios/siol) for more information. https://www.houzz.com/magazine/glamour-ahead-get-in-on-the-2013-san-francisco-decorator-showcase-stsetivw-vs~10467179?vm=thumbs

You can put wooly pockets on the wall , they have their own drip system.

I found this link to plants on walls: http://www.plantsonwalls.com
They have a watering system on a timer.