Several forms of substrate can be distinguished. Potting soil is one of them. Potting soil is a mixture of natural raw materials, to which fertilizers are added. The composition is tailored to the plant and the growing conditions. At Urban Gardening Store we have a selection of the most famous and qualitative substrates.
Another substrate form is rock wool. This is also a natural product, which is made from basalt (solidified lava). Coconut is a more newer variant, which is increasingly used in horticulture. Coconut is also used as an additive for the potting soil substrates.