A vertical pole (2) holds plant growing containers (3, 50, 54), at multiple heights. Some containers may be mounted at a given height (H1-H9) in a circular array around the pole. Each container may occupy a V-shaped region about the pole in a top view. The pole may be moveable by a conveyor system (4, 5). The pole may have a fluid reservoir (30), and a fluid distribution system (31-35) extending from the fluid reservoir to plant growing containers at different vertical locations on the pole. Each plant growing container may integrate a soil containment portion (51), a bottom drain portion (61) that collects fluid draining through the soil, and a bypass drain portion (64, 70, 72, 75, 79), that interconnects with higher and lower like containers on the pole and bypasses the soil in the containers for rinsing the soils individually.