Abstract: There is disclosed a device for holding and growing plant material by hydroponic techniques, the device including a tray having sloping sidewalls, with the sidewalls having extensions for being supported on a rail, and a corrugated bottom with the corrugations shaped to provide drainage of liquid from the bottom of the tray and to hold a water-impervious, seed-holding membrane above the corrugations so that the membrane will have a crown that causes liquid to drain toward the edges of the tray.

Abstract: There is disclosed a device for hydroponic growth of plants which includes an elongated chamber having an inlet door, an outlet door, and an interior designed to support vertically spaced trays which are arranged to be advanced one tray-length each day from the inlet door toward the outlet door. The trays are illuminated with light adapted to promote photosynthesis after advancing three tray-lengths through the chamber. The chamber is at least seven tray-lengths long and is provided with sprays above the top row of trays. The trays have corrugated bottoms with drain holes in the lowermost portion of each corrugation.