Perlite

Perlite is a lightweight, sterile and porous material derived from volcanic rock. In the horticultural industry, it is primarily used as a soil amendment to improve aeration and drainage in growing media. Perlite is produced by heating the volcanic rock to high temperatures, causing it to ‘pop’ and form white, puffed granules. These granules have a neutral pH and are chemically inert, making them ideal for use in a variety of growing environments, from container gardening to hydroponics.  

Perlite is often mixed with other media like peat moss, coconut coir or vermiculite to create balanced growing media tailored to the specific needs of different plants. Its versatility makes it an essential ingredient in many horticultural soil mixes, from seed germination to large-scale agricultural production. In high-tech vegetable cultivation, perlite is even used 100% as a hydroponic substrate. 

Perlite is often compared to vermiculite, another common growing medium. While both improve aeration and drainage, perlite is more focused on improving drainage, while vermiculite excels in moisture retention and nutrient buffering. 

• Aeration: The porous nature of perlite creates air pockets within the soil or growing medium, which supports healthy root development by enhancing oxygen availability.

• Improved Drainage: Perlite helps prevent soil compaction and allows excess water to drain freely, reducing the risk of root rot and improving oxygen flow to plant roots.

• Lightweight: Perlite is much lighter than other soil amendments like sand or clay, making it ideal for container gardening, raised beds, rooftop gardens and other setups where weight is a consideration.

• pH Neutral and Sterile: Perlite is naturally sterile and free from diseases, pests, and weed seeds. It has a neutral pH, making it a safe and reliable addition to potting mixes or hydroponic systems.

• Water Retention: Despite its drainage properties, perlite can retain some moisture, which can be beneficial for plants that need consistent but not overly saturated soil.

• Versatile Application: Ideal for use in seed starting, hydroponics, container gardening, and soil conditioning. It can also be used as a rooting medium for cuttings and as a component in potting mixes.

• Long-lasting: Perlite does not decompose or break down over time, providing long-term benefits to soil structure and plant health.

• Soil Amendment: Mix perlite into your soil at a ratio of 10-50%, depending on your specific needs and plant requirements. For heavy clay soils, a higher percentage of perlite will improve aeration and drainage.

• Seed Starting: Use perlite alone or mixed with peat moss or vermiculite to create a sterile, well-draining medium for germinating seeds.

• Container Gardening: Add perlite to potting mixes to improve drainage and aeration, ensuring optimal conditions for container-grown plants.

The grade that is available for sale is the 1-8 mm coarse variety.