Hydroponics is a subset of hydroculture, which is a method of growing plants without soil, by instead using mineral nutrient solutions in a water solvent.
HISTORY:
The word hydroponics comes from the roots “hydro”, meaning water, and “ponos”, meaning labor, this method of gardening does not use soil.
The earliest modern reference to hydroponics (last 100 years) was by a man named William Frederick Gericke. While working at the University of California, Berkeley, he began to popularize the idea that plants could be grown in a solution of nutrients and water instead of soil.
Gericke declared them wrong by successfully growing 25-foot tall tomato plants in nutrient-filled solutions.
After World War II, Hydroponic cultivation was still used widely by the military. The U.S. army planted a 22 ha at Chofu, Japan.
In the 1950s, the soilless method of Hydroponics expanded to a variety of countries including England, France, Italy, Spain, Sweden, the USSR, and Israel.
Types of Hydroponic Systems
The cool thing about hydroponics is that there are many different types of hydroponics systems available. Some of the best hydroponic systems on the market combine different types of hydroponics into one hybrid hydroponic system. Hydroponics is unique in that there are multiple techniques you can use to get the nutrient solution to your plants.
1) Deepwater Culture
Deepwater Culture (DWC), also known as the reservoir method, is by far the easiest method for growing plants with hydroponics. In a Deepwater Culture hydroponic system, the roots are suspended in a nutrient solution. An aquarium air pump oxygenates the nutrient solution, this keeps the roots of the plants from drowning. Remember to prevent light from penetrating your system, as this can cause algae to grow. This will wreak havoc on your system.
2) Nutrient Film Technique
Nutrient Film Techinque, or NFT, is a type of hydroponic system where a continous flow of nutrient solution runs over the plants roots. This type of solution is on a slight tilt so that the nutrient solution will flow with the force of gravity.
3) Aeroponics
Aeroponics is a hydroponics method by which the roots are misted with a nutrient solution while suspended in the air. There are two primary methods to get the solution to the exposed roots. The first method involves a fine spray nozzle to mist the roots. The second method uses what’s called a pond fogger. If you decide to use a pond fogger then make sure you use a Teflon coated disc, as this will reduce the amount of maintenance required.
4) Wicking
Wicking is one of the easiest and lowest costing methods of hydroponics. The concept behind wicking is that you have a material, such as cotton, that is surrounded by a growing medium with one end of the wick material placed in the nutrient solution. The solution is then wicked to the roots of the plant.
5) Ebb & Flow
An ebb & flow hydroponics system, also known as a flood and drain system, is a great system for growing plants with hydroponics. This type of system functions by flooding the growing area with the nutrient solution at specific intervals. The nutrient solution then slowly drains back into the reservoir. The pump is hooked to a timer, so the process repeats itself at specific intervals so that your plants get the desired amount of nutrients.
6) Drip System
A hydroponic drip system is rather simple. A drip system works by providing a slow feed of nutrient solution to the hydroponics medium. We recommend using a slow draining medium, such as Rockwool, coconut coir, or peat moss. You can also use a faster draining medium, although you will have to use a faster dripping emitter.

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Hydroponics: Beginner's Guide (Part 1)