A gravity-driven plant cultivation system includes: (a) a frame; (b) a plurality of vertically stacked conveyor assemblies mounted to the frame. Each conveyor assembly includes at least one gravity conveyor extending along a conveyor axis. The conveyor axis slopes downwards relative to a horizontal plane from a frame upstream end to a frame downstream end of the frame. The system further includes (c) a plurality of plant cultivation trays rollingly supported on each gravity conveyor and urged to translate along a respective conveyor axis toward the frame downstream end via gravitational force.