What is Hydroponics

Hydroponics is the production of plants in a soilless medium whereby all of the nutrients supplied to the crop are dissolved in water. Liquid hydroponic systems employ the nutrient film technique (NFT), floating rafts, and noncirculating water culture. Aggregate hydroponic systems employ inert, organic, and mixed media contained in bag, trough, trench, pipe, or bench setups. Aggregate media used in these systems include perlite, vermiculite, gravel, sand, expanded clay, peat, and sawdust. Normally, hydroponic plants are fertigated (soluble fertilizers injected into irrigation water) on a periodical cycle to maintain moist roots and provide a constant supply of nutrients. These hydroponic nutrients are usually derived from synthetic commercial fertilizers, such as calcium nitrate, that are highly soluble in water. However, hydro-organics—based on soluble organic fertilizers such as fish hydrosylate— is an emerging practice. Hydroponic recipes are based on chemical formulations that deliver precise concentrations of mineral elements. The controlled delivery of nutrients, water, and environmental modifications under greenhouse conditions is a major reason why hydroponics is so successful.

Advantages and Disadvantages of Hydroponics

Hydroponically produced vegetables can be of high quality and need little washing.Hydroponic production is management, capital and labour intensive.
Soil preparation and weeding is reduced or eliminated.A high level of expertise is required.
It is possible to produce very high yields of vegetables on a small area because an environment optimal for plant growth is created. All the nutrients and water that the plants need, are available at all times.Daily attention is necessary.
One does not need good soil to grow vegetables.Specially formulated, soluble nutrients must always be used.
Water is used efficiently.Pests and diseases remain a big risk.
Pollution of soil with unused nutrients is greatly reduced

The difference between hydroponic vegetable production and production in soil


Field production

No soil is required.

Good topsoil is required.

Good soil = good drainage, compost, disease-free.

Plants are irrigated automatically.

No water stress.

Plants need to be irrigated to minimise water stress

Nutrients are available at all times

Only soluble fertilizers are used.

Hydroponic fertilizer formulations contain a balanced nutrient content

Nutrients must be added to soil.

Unless a laboratory analysis is done, too much or too little nutrients can be added.

Soil borne diseases can be eliminated

Soil borne diseases can build up in the soil.

Hydroponic production is not organic because artificial nutrients are always used and plants are usually not grown in soil.

It is possible to produce organic vegetables in soil because one can use organic fertilizers such as compost and manure.

What do I need to start?

    Important requirements
  • Source of clean water
  • The right location
  • Specially formulated fertilizer
  • Time to attend to the system daily
  • A little knowledge of plants or gardening
  • A commercial or home made unit

Know the basics

To be able to produce vegetables successfully year after year, one needs to be familiar with the basics of hydroponics. Know about the plant, growth medium, water & nutrients. By relying on recipes only, one will not be able to identify the cause of a problem and you may not be able to correct them.