by Eliza Holcombe Lord, Master Gardener, Master Naturalist, Permaculturist
It’s never the wrong season to improve garden soil, but fall and early winter are particularly ideal for this task.
In forests, fall is the time of year that trees “fertilize” themselves and their understory plants by dropping an abundance of carbon in the form of leaves and dead limbs. The microbes and fungi in the soil thrive on this heavy supply of organic matter, creating nutritious soil for surrounding plants.
Gardeners can take advantage of this natural process by mimicking the forest floor in their garden beds. That’s why you’ll never see a pile of leaves by the street in a good gardener’s yard–instead they convert their fallen leaves into rich, living garden soil that growths healthy, nutrient-dense plants.
How to Turn Fall Leaves Into Spring Soil
When using large leaves, mix them with small twigs to keep them from matting together into an impermeable mat. Alternately, you can shred them first using a chipper, lawnmower, or chickens. You can also mix them with wood chips — any mixture that prevents matting will work. Leaves can be added very thickly to garden beds as long as they are not allowed to sit against the trunks and stems of plants, which can cause rot. In spite of conventional admonitions, which are largely unfounded, a mulch depth of up to 12” in most garden beds is highly desirable.
So, if you want to have rich, healthy garden soil, take advantage of all those fallen leaves and other yard debris. Healthier soil = healthier plants = better yields of more nutrient-dense foods.