A method for installing a cultivation floor system comprising a floor on which plant containers are placed, which cultivation floor system comprises an ebb/flood watering installation which is configured to alternately cause a supply of water to the cultivation floor and a discharge of water from the cultivation floor. The method comprises: - providing a watertight basin; - placing one or more irrigation lines in the basin, which irrigation lines provide several outflow openings along their length which make it possible for water to flow from the one or more irrigation lines; - providing a water pump and connecting that water pump to the one or more irrigation lines; - providing a water-permeable structure in the basin, which structure has a permeable and horizontal top which forms the floor on which plant containers are placed, which structure comprises one or more layers of granular material, wherein the one or more irrigation lines are covered by the permeable structure.