Hydroponics is a farming method of growing crops in a soil-less or an aquatic-based environment. Hydroponics involves using nutrient solutions dissolved in a water solvent to feed the vegetables without soil. The farmers plant the terrestrial crops with their roots supported by a medium like gravel and perlite, or they are left exposed to the minerals. These nutrients can be obtained from different sources including natural nutrients, duck manure, and fish waste.
History of Hydroponics
The earliest publication on hydroponic was the book called ‘’sylva sylvarum’’ which means ‘’natural history" by Bacon Francis in 1627. Later in 1699, Woodward published his water culture experiments. The creation of 9 crucial elements which support soil-less farming by 1842 and the discoveries by Wilhelm Knop and Julius Sach (who were German botanists) resulted in the creation of the soil-less farming technique. William Frederick began publicizing the soil-less farming technique which he called aquaculture in 1929. William introduced the term ‘’hydroponics’’ in 1937. The earliest successful hydroponic farming was done in Wake Island during the 1930s to grow vegetables for the passengers passing through the island.
Different Types of Hydroponic Techniques
There are two variations of the mediums; the top-irrigation and the sub-irrigation. For all the techniques, the reservoirs are made using plastic, wood, solids, metal, glass, and concrete. The growth of algae and fungi stop by keeping the container away from the light. Some of the hydroponic techniques include:
Static Solution Culture
Static solution culture involves farmers planting crops in containers like tanks, tubs, plastic buckets, and mason jars partially filled with the nutrient solution. For un-aerated cultures, the solution level is kept low enough for the roots to get adequate oxygen. With this type of technique, the farmer plants only one crop per reservoir. The size of the container depends on the size of the plant. All the clear-jars must be covered with black plastic or an aluminum foil to help exclude sunlight. The solution can be replaced once per week or when the nutrient concentration level reduces below a level given by the electrical-conductivity meter.
Aeroponics is a technique whereby the farmer exposes the plant’s roots discontinuously and continuously in an environment saturated by droplets of the nutrient solution. Aeroponics entails planting the crops with their roots suspended in air or in a chamber where they are wetted periodically with the atomized nutrients. The main benefit of this technique over the others is that the roots are perfectly aerated.
Continuous-flow Solution Culture
With this method, the nutrients are allowed to flow continuously past the crop’s roots. Automating this system is simpler as compared to the static culture because of temperature adjustments, sampling, and nutrient. A correctly designed continuous-flow culture uses the correct flow rate, channel length, and channel slope. The main benefit of this technique over the others is that the roots are exposed to adequate nutrient supply, water, and oxygen.
Fogponics is a type of aeroponics which involves the nutrient being aerosolized by the vibrating diaphragm at ultrasonic frequencies. The small-sized droplets can diffuse in the air quickly and help deliver the nutrient to the roots without affecting the access to oxygen.