The advantages of using DNA Mills Ultimate Soil with Cork: Manufactured using high grade, 100% natural raw ingredients Cork allows rapid root development and high aeration (additional perlite not required) Combined with Mills Organic Nutrients to supply a natural base feed to your plants No additional nutrients required for around 4-6 weeks Ready to use both indoors and outdoors DNA Mills Ultimate Soil with Cork is also an eco-friendly growth medium as harvesting cork can prolong the life of cork oak trees, for example if left unharvested, they can die within 100 years, but if regularly harvested every 9-12 years, this can triple the lifespan of the tree, allowing them to live for 300+ years. The cork oak tree forests of Europe are also responsible for absorbing millions of tons of CO2 (carbon dioxide) along with generating equal amounts of O2 (oxygen) making them one of the most sustainable and environmentally harvested forests in the world. Using cork actually saves trees as it prolongs their life span while helping to generate the air we breath. DNA Mills Ultimate Soil with Cork is available in 50 Litre bags.