Technical Background

Hydroponics is an innovative method of plant cultivation in which crops grow without soil – using very little water and sometimes vertically on walls or in multi-level installations – directly in a nutrient solution. This enables precise control over nutrients, water, and environmental factors, resulting in rapid growth, high yields, and efficient resource use. Hydroponics is particularly suitable for schools and beginning “urban farmers,” as it provides an engaging, hands-on way to explore the basics of plant biology with limited resources.

There are various approaches, but they all rely on similar system components (see Figure 1). The reservoir can be seen as the heart of the system, circulating water and nutrients to supply the plants with everything they need. Depending on the system, it may be necessary or useful to aerate the reservoir because water holds less oxygen than air. Light is another critical factor for productivity, coming from natural or artificial sources depending on location. Finally, the choice of crops is decisive, as each plant has different requirements for the system and environment.