Hydroponics (from the Greek words hydros, meaning water and ponos, meaning labor) is a method by which plants are grown in a nutrient solution without soil. Nowadays, the term hydroponics also encompasses soilless plant growth, i.e., growth on inert solid substrata like sand, gravel, etc. Hydroponics developed from the understanding of the role of different substances supporting the growth of plants. Such work on plant constituents dates back to the 16th century.
History of Hydroponics
Hydroponics is as old as the Pyramids. As a farming tool, it was successfully used by Greeks and the Hanging Gardens of Babylon were the most successful attempts at growing plants hydroponically. But it was the Aztecs who are regarded as the first people in the world to develop the art and science of hydroponics. Driven away from their area to a place with no arable land, this brilliant race developed large water fields by growing crop plants on rafts made up of bushes and reeds called Chinampas. Many such chinampas were sometimes tied together to form floating islands of two hundred feet or longer.
This method was scientifically developed by two German scientists, Julius von Sachs (1860), professor of Botany at the University of Wurzburg (1832-1897), and W. Knop (1861), an agricultural chemist. Knop has been called ‘The Father of Water Culture.’ In 1860, Sachs gave the first standard formula for a nutrient solution in which plants can be grown successfully. A hydroponic nutrient solution should essentially contain water, dissolved oxygen and carbon (C), nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), sulfur (S) (macro elements), iron (Fe), manganese (Mn), boron (B), copper Cu), zinc (Zn), molybdenum (Mo), and chlorine (Cl) (micro elements).
Nutrients
Plants, when they grow in soil, do not use it for their growth. Soil only holds the nutrients required by the plants to grow. They also provide physical support to the plants. In soil, water and nutrients are scattered randomly and thus the plant has to expend a lot of energy to grow roots to reach these sources. This makes hydroponics sound naturally logical, since here plants are provided with all the necessary nutrients in water. And thus the plant has to use less energy in the uptake of these nutrients.
The solution should be pH balanced and properly buffered so as to prevent the drifting of the pH to acidic or alkaline conditions. Nutrient mixtures available in the market are of two types – solid (powder) and liquid (solution). The powder nutrients are more concentrated than the liquid ones and are relatively inexpensive. The powder needs to be completely dissolved in hot water before adding to the tank. Liquid nutrients, though a bit costly, are more popular with gardeners due to its ease of use. They can be directly added to the tank. (Hydroponics B.C.)
Advantages
Today, hydroponics is regarded as an established science. Experiments in many countries have revealed the ease of the method and its advantages. Hydroponically grown crop plants have consistently given more yields as compared to the non-hydroponic average. Hydroponics can be practiced in places where natural agriculture is not possible, like in deserts or in space stations. People living in highly populated cities can now grow fresh vegetables in window-boxes or rooftops using hydroponics.
Hydroponically grown plants grow faster and are relatively free of soil-borne diseases. They require less growing area, less cost and negligible manual work. It should be appreciated that hydroponics has the capability to solve the world’s food problems. It has been hailed by the Forbes Magazine and the Los Angeles Times as a most spectacular, current breakthrough yet. Hydroponics is not a recent development in scientific technology but a technique adopted and adapted by humans from Nature. The earliest plants on this planet grew hydroponically and more than half of all plant life grows hydroponically – in seas and oceans.
Hydroponics is a simple and cost effective method to grow plants and must be exploited heavily to solve the food shortages of the world. As the Bengal System of hydroponics in India has shown that it could be easily adapted to even the most peculiar problems of the subcontinent, this system could be a boon for developing and under-developed nations who face the brunt of the food shortages and where millions die every year due to starvation or malnutrition.
