Biowall at Dansko corporate headquarters - Photo - Leader-Telegram online

Soil removed the plants are now growing as epiphytes (air plants).

Planned four-story biowall at Drexel University
The bottom two photos are from an interesting Philadelphia Inquirer article about plant walls inside buildings. They are also called green walls, living walls and vertical gardens...take your pick.
In this case, it is appropriate to call them biowalls since they have an air-cleaning function beyond their decorative properties. Some call them active green walls. What makes them active is fan-assisted air circulation through the plant wall. That is how the air cleaning is accomplished.
It is interesting to see how commonly available soil-grown houseplants are used. They wash the soil from the root system and install the plants in a double thickness of fabric as shown in the middle photo.
The fabric is irrigated from above and the water then travels down to each plant. These terrestrial plants are essentially growing in a hydroponics environment in the biowall.
This is similar to the system used by Kamal Meattle in the Paharpur Business Center in Delhi, India. His TED presentation has been the subject of much blogger buzz about how three species of "magical air cleaning" plants can clean the air in your home. This is junk science.
What is not said in his TED presentation is that all of the plants are in one room. Apparently, his plant room does essentially the same thing as these biowalls. See this prior post.