Volcanic stone roughly 2-10 mm

Excellent purely mineral soil, mixture of lava, pumice and the highest quality zeolite. Grain 2 - 10 mm.

Particularly suitable for larger pots and closed irrigation systems. Excellent water and air flow is achieved through the grain size.

Zeolite is a framework silicate; its outstanding capabilities are due to its mineralogical structure. One of the special properties of zeolites is their high and reversible cation exchange capacity (KAK). To compensate for the negative charge on the crystal lattice, ions are adsorbed on the outer and inner surfaces of the crystal lattice. The cations can be replaced by ammonium or heavy metal cations, for example. The minerals of the zeolite group are characterized by a pronounced selectivity for various cations. The bond to certain heavy metals, such as lead, is particularly strong, whereas the bond to naturally occurring cations (sodium, calcium) is weak. Cations such as potassium and ammonium occupy a middle position. The adsorption of heavy metal or ammonium ions, for example, is always associated with the exchange of the ions present.

With fertilization, nutrients such as ammonium or potassium are enriched in the soil solution. This high nutrient content, which can usually not be completely absorbed by the plants immediately, is offset by a low concentration in the zeolite. Some of the nutrients are adsorbed in the crystal lattice of the zeolites and in this form are protected from decomposition / conversion or leaching. If the concentration of nutrients in the soil solution drops, the zeolites release the nutrients again so that they can be absorbed by the plants. Zeolites do not change their physical properties through ion exchange. We use zeolites from the clinoptilolite group.