Book excerpt: Bio-activated charcoal — called biochar — is the new darling of organic gardeners, embraced for its outstanding abilities to enrich the soil and improve plant growth. Gardening with Biochar is the first comprehensive guide to understanding, making, and using it effectively in the home garden. In this highly accessible handbook, long-time garden writer Jeff Cox explains what biochar is and provides detailed instructions for how it can be made from wood or other kinds of plant material, along with specific guidelines for using it to enrich soil, prevent erosion, and enhance plant growth. Now widely available at garden centers, biochar is also being lauded for its ability to sequester carbon in the soil, making it good for the health of the planet as well as the plants.