Ebb and flow bench is a cultivation bed with a plastic structure and a tidal seedling tray made of plastic. It is also called a bottom irrigation cultivation bed. This ebb and flow irrigation mobile seedbed uses basically the same columns and supports as commercial metal structure cultivation beds, and the bed surface uses a molded impermeable plastic seedling tray. When irrigating, the seedling tray is filled with clean water or nutrient solution and allowed to stay for a certain period of time, so that the crops can absorb water through the drainage holes at the bottom of the flowerpot through capillary action. Irrigation water is then drained out of the cultivation bed, either collected and reused, or drained directly to local sewers.