PERTERRA is produced from the mineral perlite. Perlite is an inorganic aluminosilicate mineral of volcanic origin with 3-4% crystalline water. Expanded perlite is produced by heating to 1000°C, which causes the crystal water to evaporate. The expanded product is further processed to perfect its properties and then packaged. It is a material with grains of 1 - 5mm, very light (80-110kg/m3) which can hold 3 - 4 times its weight in water (250-300It water/m3). The material is completely free of disease and weed seeds, and it also acts as a temperature stabilizer. It is chemically inert and has a neutral pH (6.5 - 7.5). It does not rot or melt and has an unlimited lifespan. It has the ability to regulate the correct ratio of air and water in the soil mixture, ensuring ideal drainage conditions, for uniform development of the root system.