Hydroponics is a subset of hydroculture, which is a method of growing plants without soil by instead using mineral nutrient solutions in a water solvent. Terrestrial plants may be grown with only their roots exposed to the nutritious liquid, or the roots may be physically supported by an inert medium such as perlite or gravel.

The nutrients used in hydroponic systems can come from an array of different sources, including (but not limited to) byproduct from fish excrement, duck manure, or purchased chemical fertilizers.