This ancient soil amendment, known as Terra Preta, provides a microbial habitat to your soil for hundreds of years. Microbes attach themselves to the millions of crevices and cracks in this 100% carbon substance. Biochar acts like a microbial megacity! It is known that 1 gram of biochar has the surface area of 2 soccer fields. That's an immense amount of surface area for millions of soil bacteria, fungi, and other microbes to live and thrive in. If you are looking to transform your garden from clay to rich, black earth, Soil House Inoculated Biochar can help you turn dead soil back into a thriving ecosystem. We recommend 5 lbs of biochar for each cubic yard of garden soil or compost. Amend twice per year (once in the spring and once in the autumn) by either using a broadfork or tiller to mix it into the soil.