The source of the word hydroponics is from Greek: hydro – water and ponics – work.
Growing plants without soil is nothing new. There is some evidence of ancient civilizations farming in water-based farming methods:
The Hanging Gardens of Babylon are one of the seven wonders of the ancient world. Legend has it that King Nebuchadnezzar II built the gardens as a gift to his wife Amitis about 600 BC. The gardens were irrigated with water from the nearby Euphrates River, which were raised up by an Archimedes screw mechanism.
The Aztecs in Central America developed a creative way to deal with the hostility of neighboring tribes and the shortage of arable land. They built floating rafts from reeds called chinampas.
These rafts were loaded with nutrient rich sediment, taken from the bottom of the lake, where vegetables, flowers and even trees were planted. The roots of the plants penetrated the raft and provided the plants with a permanent source of water.
Hydroponics in the modern era began developing following a better scientific understanding of the conditions required for plants to grow and development of nutrient solutions for growing, alongside technological developments that greatly improved the growth systems such as the availability of plastic products and water pumps.
Hydroponic systems are usually closed systems – that is, the nutrient rich water flows in a closed circuit.
There are many different designs for hydroponics systems, but the three main methods of growing are: Growing in NFT tubes. In this method plants are placed in holes in a pipe of a large diameter, with nutrient rich water flowing down the tube in a thin stream, thus nourishing the roots of the plants.
Floating Rafts – In this method we plant in holes on the floating surface (usually polystyrene) over a relatively large water body containing nutrients.
Flooding and draining – plants are planted in an inert substrate such as tuff or hydrotone. The grow bed is filled and emptied intermittently using a siphon mechanism.
During the draining, oxygen enters the root zone.
Water saving – As mentioned above, in most Hydroponics systems, the water flows regularly and is consumed only by plants and evaporation, unlike soil based cultivation methods in which most of the water is ‘wasted’ in the soil.
This is a significant saving of up to 80% of the quantity of water.
According to the International Food Organization, about 70% of global freshwater consumption is being used in agriculture.
With the increase in the Earth’s population, alongside worrisome phenomena such as global warming, desertification and the depletion of water resources, it is clear that a need for a modern farming system such as hydroponics exists.
Saving space – Since all the nutrients and water reach the roots of the plant directly, there is no need for the plant to develop a root system as large as in soil. Therefore plants can be grown at a higher density. In addition, not relying on land allows growing upwards utilizing the vertical space. As a result, more vegetables can be grown per area unit compared to soil.
There is no need for weeding
Reduced fertilizers usage – Just like saving water, the main savings in fertilizers is due to the flow of fluids in the system.
In addition to the financial significance (less fertilizer is ‘wasted’ by soil infiltration or chemical interactions) there is also a clear environmental advantage.
Traditional agriculture is responsible for nitrogen and phosphorus pollution in saline and freshwater sources. Leakage of these substances into the environment leads to contamination of drinking water sources and damage to the marine environment.
A Shorter life cycle – In Hydroponics
the plant receives everything it needs directly to the roots in a readily available way, unlike in soil where the roots compete with other factors (such as bacteria)for nutrients. As a result, the growing cycle will be shorter in a hydroponic system than in traditional soil cultivation.
Easy and convenient harvesting – The modular growing systems can be easily adapted for user comfort. Plant level at waist height will save a lot of effort for harvesting. The systems can also be adapted to people with disabilities, children and the elderly.