A plant growing apparatus of a hydroponic and/or aeroponic plant growing system includes a support assembly and a pair of height control mechanisms. The support assembly includes a bottom platform, supported and mobilized by corner caster wheel devices, and top and intermediate platforms, vertically spaced apart from one another and the bottom platform by upright corner posts rigidly affixed at the corners of the bottom platform. The intermediate platform may be manually raised or lowered along the posts. The height control mechanisms are concurrently operable to raise or lower the top platform along the posts. In addition to the plant growing apparatus, the plant growing system also includes light modules supported by the top platform, plant grow cells supported by the intermediate platform below the light modules, and a water reservoir and pump on the bottom platform and connected in communication with the plant grow cells and height control mechanisms.
