Abstract: Hanging stacked plant holders and watering systems for receiving and supporting a plurality of pots in pot holding rings fastened to the end of a plurality of unit arms. The unit arms are stacked on a structure that includes an upper manifold and a lower manifold. The pots supported by the upper unit arms receive water from the upper manifold, and the pots supported by the lower unit arms receive water seeping through the upper pots, with water seeping through the lower pots being collected for recirculation. various features and construction details are disclosed.