How to Use Hydroponic Growing Systems

The choice of an appropriate hydroponic growing system depends on the type of plants, the scale of the growing unit, and the expense and time that the grower is ready to invest. Described below are some hydroponic growing systems:

Wick system. This is the most basic hydroponic growing system. It makes use of an absorbent 'wick' such as a nylon rope suspended between the growing medium of the plants and a reservoir of nutrient solution. The wick draws in nutrients based on how soon the plants absorb it. A suitably absorbent medium is needed for this system such as a combination of perlite with either vermiculite or coconut coir. This system can be built using simple materials at home and is ideal for hobby growers having few plants.

Reservoir system. This is another simple hydroponic growing system that is somewhat more advanced. Instead of a wick, the plant containers are directly placed in the reservoir of nutrient solution. An air pump is used to keep the nutrient solution aerated with oxygen. This system can be used with mediums having limited absorbing properties, such as volcanic chips or clay pellets combined with vermiculite. This system is inexpensive to set up and easy to maintain, but may lead to a root rot situation as the plants are always submerged in the water so much aeration is required for the reservoir full of water.

Flood and drain system. In this system, the plant container is separated from the nutrient reservoir below. A pump attached to a timer is used to periodically draw up the solution into the plant container and flood the roots before being drained out. It is important to set the flood drain cycle to suit the growing medium. Less absorbent mediums, such as clay pellets or perlite, may require flooding for 5 minutes, 10 times a day. More absorbent mediums, such as rockwool, will require less flooding. This popular hydroponic growing system is used by both hobby and professional growers. It can easily be built at home at little cost.

Drip system. In this hydroponic growing system, the nutrient solution is fed to plants from above using thin tubes. The flow is controlled using different emitters. More absorbent mediums require a slower drip as compared to less absorbent ones. This is an advanced system that can serve the needs of the serious hobby and commercial grower. It cannot be used with organic nutrients that can clog the emitters.

The Nutrient Film Technique (NFT). This hydroponic growing system involves using a running thin stream of nutrient solution flowing through the plant roots. This system is good for larger growing units and can easily be set up at home. However, it is only ideal for plants with a root system that is large enough to benefit from the flowing stream.

Aeroponic system. In this hydroponics growing system, the roots of the plants grow in the air, suspended above a reservoir containing the nutrient solution. A pump is used to spray the roots through tubes with a fine mist of oxygenated solution. While it is an excellent system for advanced hydroponic gardening, it requires the most attention. Also, it requires regular maintenance. As with the drip system, it cannot be used with organic nutrients.

Ryan Karl is an expert horticulturist who writes extensively on gardening topics. He is especially interested in all aspects of hydroponics, or the science of soilless gardening.