What is Hydroponic Gardening? Hydroponic gardening is a method of growing plants without the use of soil. There are two main categories of hydroponic growing: liquid and aggregate. The liquid method uses no growing medium; the plant is merely suspended over the nutrient solution so that its roots may absorb the needed elements. The aggregate system has the plant supported by a sterile, solid yet porous growing medium, but again the roots are bathed with a nutrient solution to provide their nutritional needs. All of the nutrients that the plant will require to grow are provided for in the liquid nutrient solution which is periodically provided to the plant by a variety of meth