idea and photo source: http://www.gardentowerproject.com/index.php/50-plants-in-4-square-feet
This vertical garden contains it’s very own internal worm farm, vermicomposter. The worms are fed inside a cylinder which has holes for them to pass through and lay castings around the plants roots. It’s really a hybrid version of the Underground Worm farm. As you can see from the images this works a treat and produces a ton of food.