wisdom tells us that mechanically tilling a garden is a good way to aerate and lighten the soil structure while killing weeds at the same time. But it also wreaks havoc on soil life, disturbing the local microbiome and killing a host of beneficial bacteria, fungi, and insects. The no-dig system is actually a clever method of building the soil through layering, adding a selection of natural materials that includes cellulose from paper, chopped leaves, compost, and grass clippings to increase the volume in a lasagna-like soil casserole.