I was at Cal Poly Pomona the other day and saw this interesting display. The school has several small farm plots that demonstrate innovative or new practices, from hydroponic lettuce to intensive mini-orchards and now this strange setup. They sell the produce at the adjacent farm store. From looking at it I can tell that this setup is meant to utilize vertical space and grow vegetables in a small footprint. Water drips down from the top, irrigating multiple plants on its way down. The plants are not only stacked vertically, but radiate around the central axis, maximizing horizontal space as well. In this photo they are growing hot chili peppers. I also saw basil and sweet peppers and there were others I can’t recall right now. I’m inspired to try to build one at home, since I’m always running out of space for my plants.