Substrates for hydroponic cultivation

Although it seems like a very new system, hydroponics has a long history. There are sources that date this growing technique to around 380 BC, when the Aztecs began to make the first fertiliser solutions without using soil as a growing medium. Today, this cultivation system has evolved to unsuspected levels and is one of the most advanced horticultural techniques. 

Characteristics of hydroponics substrates

Hydroponic substrates must carry out the important task of supporting the plant so that the roots come into direct contact with the water or nutrient solution. In this way, the root system of the plants can develop effectively: the roots remain protected from the light, so that conditions similar to those that the root would have in soil cultivation are recreated. 

Within the different possibilities of substrates for hydroponics, one can find organic substrates, with the presence of fungi and basic nutrients for plant growth. But it is also possible to find inert types of substrates for hydroponics, those that do not have a nutrient load and are designed for the grower to add the nutrients necessary for each plant species to the nutrient solution. 

Regardless of the type of substrate used, it is important that it provides an adequate level of oxygenation to the root system. Otherwise, the roots would not be able to develop properly and penetrate the nutrient solution, which would not guarantee an adequate supply of nutrients to the crop. 

Types of substrates for hydroponics

At Experiencia Natural it is possible to find the best selection of substrates for hydroponics from the best manufacturers and of the best quality.

Firstly, arlite or expanded clay is the hydroponic substrate par excellence, as it is specially designed for this type of growing medium. Arlite has the shape of small balls and promotes optimal oxygenation in the substrate. In this substrate the roots tend to expand optimally if the water flow in the hydroponics is well established. 

In addition to oxygenation, arlite allows for excellent drainage in the culture. Thus, with this substrate for hydroponics, the grower will prevent water from being retained in the roots and substrate and eventually rotting the root system. It is a very clean substrate, as it prevents the accumulation of algae in the nutrient solution. Furthermore, arlite is reusable, making it a type of medium that is compatible with organic farming. 

Rockwool also gives excellent results in hydroponic media. This is a widely used cultivation method because it also promotes excellent oxygenation and water retention. However, rockwool requires a little more experience in installation than arlite, for example. Thus, it is necessary to moisten the rockwool block, the format in which the substrate comes in, to make room for the material that will be used to support the plants.

Finally, coconut fibre can also be used as a hydroponic substrate. This type of substrate comes from the fibre between the fruit and the coconut husk. It is a totally ecological hydroponic substrate, with high oxygenation and facilitates water drainage.