Abstract: A collapsible support structure for supporting and transporting a plurality of plant culture trays. The structure comprises a rectangular frame having at least two spaced parallel support tracks for receiving end portions of culture trays therebetween. Each track has an outer wall and are secured at their ends to opposed end walls. A retractable leg assembly is secured on adjacent ends of the frame and pivotally connected thereto and displaceable from the underside thereof whereby the leg assembly may be displaced from a support position wherein the frame is supported elevated from a ground surface by the leg assembly to a collapsed position wherein the leg assembly is located entirely within the frame. A retention slot releasably retains the leg assembly within the frame.