A hydroponic gardening system includes an apparatus for supporting the growth of selected plants, which apparatus includes a housing having lower level nutrient tank (15) and a plant support tray (20) with a dual-level aeration chamber therein. Seed germination cubes (12) are positioned on the tray adjacent the aeration chambers, and a uniquely designed capillary mat (40) overlies the floor in both levels of the aeration chamber and underneath the seed germination cubes. An end portion of the capillary mat extends down into the nutrient tank. Nutrient is conducted from the tank through the capillary mat to the plant root system in the aeration chambers. While the root system is nourished by the capillary flow of nutrient fluids, the structure of the dual-level aeration chamber is such that the roots are maintained in an environment of freely circulating air and conditions of 100 percent humidity.
