Description

Perlite is a naturally occurring silicaceous volcanic rock which has been heated in a furnace to create lightweight particles with a honeycomb of internal cells and a high surface area. The multi-cellular structure affords a very high pore volume, typically 97% of total volume. Pores may be filled with air or water, depending on size. Large pores drain freely and are air-filled, medium pores contain water which is easily available for plant uptake. As pores get smaller, water is held more strongly and in the smallest pores is unavailable for plant growth. The air trapped in the perlite is insulated from temperature variations and therefore helps stabilise the compost temperature. Sinclair Perlite has a neutral pH of between 6.5 – 7.5, is chemically and biologically stable and does not lock up or promote nutrient release.