Biochar as a long-term soil amendment

Biochar is charcoal produced by burning organic material (wood, crop residues) at high temperature with limited oxygen (pyrolysis). Its microscopic honeycomb structure provides permanent habitat for beneficial soil microbes, dramatically increasing the soil's biological activity and nutrient-holding capacity. Unlike compost, biochar does not decompose, persisting in soil for hundreds to thousands of years. Add biochar at 5-10% by volume of your soil mix. Critical step: raw biochar must be 'charged' before adding to soil, either by soaking in compost tea, worm casting extract, or liquid fertilizer for 24-48 hours, or by mixing it into an active compost pile for 2-4 weeks. Uncharged biochar temporarily locks up nitrogen, starving plants. Charged biochar improves water retention by 18-25%, reduces fertilizer needs over time, and increases cation exchange capacity (the soil's ability to hold and release nutrients). Cost runs $15-30 per cubic foot for quality horticultural biochar. Brands include Wakefield, Pacific Biochar, and Carbon Gold. This is a long-term investment that improves with each season.