Mulch cycling for continuous organic matter

Mulch cycling is the practice of maintaining a perpetual organic mulch layer on raised beds year-round, allowing it to decompose into the soil and regularly replenishing it from the top. This mimics the natural forest floor process where fallen leaves and debris continuously feed the soil. Keep 2-4 inches of organic mulch on the bed at all times: straw, shredded leaves, or grass clippings during the growing season, and heavier materials (wood chips, coarser leaf litter) during the off-season. As the bottom of the mulch layer decomposes, it becomes humus that integrates into the soil. Add fresh mulch on top as needed to maintain the 2-4 inch depth. Over time, this creates a self-feeding system where the soil continuously receives organic matter without any digging or amendments beyond the mulch itself. Shredded autumn leaves are the single best free mulch material for this purpose: they are abundant, decompose at an ideal rate (faster than wood chips, slower than grass clippings), and provide a balanced nutrient profile. Run a lawn mower over piles of fallen leaves to shred them (whole leaves mat together and repel water). A single large deciduous tree produces enough leaves to mulch several raised beds for a year.