Making diy biochar imho makes sense if you have dry, wood-ish material (Arundo, bamboo, branches). Otherwise you are likely to produce a lot of smoke for little

Making diy biochar imho makes sense if you have dry, wood-ish material (Arundo, bamboo, branches). Otherwise you are likely to produce a lot of smoke for little biochar. As for the garden organic waste one can tie itself in knots trying to balance this or that. In my experience shallow trench composting works just fine. You do not get a smelly pile leaking fluids, packs of slugs / swarms of flies. No extra work (mixing, distribution). Earthworms will also thank you. You may have issue with hardy weeds and rats, so you milage may vary. One can ferment the weeds in a plastic bag before buring them lowering the chance of spouting, but this is extra and quite smelly work. One can also dig deeper(+30cm of earth cover). Less chance of weeds and animals digging to snack on a rotten carrot.