Hydroponics essentially means working with water (hydro meaning water and ponos meaning labour). It is the process of growing plants without soil, either in an inert medium or no medium at all. Hydroponic mediums which are commonly used are perlite, vermiculite, rock wool, clay pebbles and coconut fibre. The food which is normally supplied by the soil is supplemented through the water and is usually dissolved mineral salts but more recently has spread to organic nutrients derived from plant and aquatic sources.
Versatility of Hydroponics
A popular phrase among hydroponic enthusiasts is any plant, anytime, anywhere. This is only the case however, when you have a controlled growing environment which will require grow lights, ventilation and temperature regulation. With hydroponics being easily adapted for inside the home it is often the case that the environment can be controlled year round and you can infact grow any plant, anytime, anywhere. Hydroponic culture is also used in many commercial applications from growing fodder year round for stock, to flowers and foods all over the world.
!!< Hydroponic Systems
There are 2 main categories that hydroponic systems fall under:
Recirculating systems Run-to-waste systems
Recirculating systems include NFT trays, reticulation systems in pots and flood and drain (ebb and flow). Run-to-waste systems are probably the most widely used forms of hydroponic systems because of their efficient use of water, these include dripper fed systems and pot culture.
Nutrient film technique is the hydroponic growing method which relies on a highly aerated thin film of water passing over the roots to provide them with the nutrition they need. Usually in thin channels or larger trays this technique is the one where we have all seen lettuce and herbs growing in commercial farms. For specific details of NFT systems, check out our range of NFT Nutriculture systems.
This type of culture relies on water being stored in a main reservoir with a pump which supplies the water to the top of the pots via drip line. The water then drains through the pots and is directed back to the reservoir to be stored before watering again, the popular Wilma 4 pot and Wilma 8 pot systems are a great starting point.
Flood and Drain
Also known as ebb and flow, this method of cultivation also has a main reservoir which is used to feed water to the bottom of the root zone. When the pump finishes its cycle the water drains back into the reservoir sucking oxygen into the root zone to allow faster absorption of food into the plants.
A lot of people have preconceptions of hydroponic growing being too complicated and technical. The reality is that pot culture can give even the novice gardener a simple and cheap method of starting out. Hydroponic pot culture is very similar to growing in soil pots as the mediums used tend to hold sufficient water to allow you to water only once a day. Using a hydroponic medium in this way allows sufficient oxygen to be present in the root zone for exceptional grow rates.
Dripper Fed Systems
Dripper systems come in a wide range of shapes and sizes. From the commercial tomato and rose gardens grown in rows in massive greenhouses to the Wilma systems with coco fibre in the pots, they suit any sized garden. Due to their relative ease and efficient use of water they are very popular. They involve a main nutrient reservoir(s) with supply lines running through the crop to individual drippers placed in the medium. This is the classic run-to-waste system and shows the true value of hydroponic culture and its sustainability for the future.
The hydroponic field continues to innovate, providing solutions that bring it more and more into the public eye. Recently you may have seen the green walls that have been popping up anywhere from the walls of office buildings to inside walls in peoples houses. These vertical gardens address many issues by acting as a thermal mass on the side of buildings, providing added insulation, as well as maximising space available for growing. Since the early days of the Aztec floating gardens, humans have used hydroponics and aquaponics to push the boundaries of society, watch this space for exciting innovations in the world of hydroponics.