The Medium Used In Organic Gardening
Organic gardening is a form of green gardening that involves the use of water as a medium for planting as opposed to soil. In hydroponics organic gardening, the water is mixed with nutrients and exposed to the roots. This mineral nutrient solution can also be put in a medium for growing the plants. Perhaps one of the most important questions a hydroponics organic farmer will ask himself is what medium to use.
There is a myriad of organic media to choose from; the hydroponics growing technique will help a farmer decide which medium to use. They all come with advantages and disadvantages. A common medium for hydroponics is using clay – expanded clay for that matter. the clay used for this medium is prepares by first shaping into pellets and then baking them at 2,190 °F (1,200 °C). Expanded clay is pH neutral inert and does not contain any nutrition. It is reusable; this means that it can be used for more than one planting season. However root matter can grow into the caly pellet themselves, compromising fresh plants.
A widely used medium is rock wool or mineral wool. It is made from basalt, molten rock spun into single filament fibers and bound into material that can support capillary action. Since it is made from rock, it is not susceptible to biodegrading. It however has been classified as a possible carcinogen.
Pozolannic lassenite is also used as material for organic farming. Some farmers use coconut coir colonized with trichoderma bacteria, which stimulates roots to grow and also protects. Coir’s water to air ratio ensures that it is not overwatered. Its high capacity for cation exchange means that unused nutrients and minerals can be stored and then released to the plants when it is required.
Several volcanic rocks are used as a medium for example pumice: a lightweight and porous rock. Perlite is a fusion of several volcanic rocks that is heated in super high temperatures until they morph into lightweight glass pebbles that are expanded. Perlite holds more water that air, and it is for this reason that some farmers mix it with soil so as to reduce soil density.
Sand and gravel are other media used by organic farmers. Sand is cheap and easy to get, it however does not hold water. Gravel on the other hand is easy to use, cheap, does not become waterlogged and is easy to keep clean.