What is the definition of hydroponics?

The definition of hydroponics is centered around the method of growing plants without soil. This technique relies on a nutrient-rich water solution, which allows plants to receive essential minerals and nutrients directly through their roots. In hydroponics, various mediums, like gravel, perlite, or even just water, can be used to support the plants, but the key aspect is that soil is not involved in the growing process. This method not only conserves water by recirculating it but also enables more precise control over nutrient delivery, leading to potentially faster plant growth and higher yields. The other options, while related to aspects of plant growth, do not capture the fundamental principle of hydroponics, which specifically eschews soil as a growing medium.