There are a lot of fallen leaves outside the window, and your view is probably the same. This carpet of dead leaves is often thought of as a nuisance, but it can become an important addition to your garden.
Tuck a 3-inch layer of leaves into beds and borders to protect roots and act as a winter mulch to repel insects. As they decompose, they add nutrients to the soil, which will strengthen your plants next spring.
Others go into the compost heap and are cooked, along with food scraps, weeds, and spent annuals and perennials, into what we gardeners call “black gold.” But there is another use for fallen leaves that you may not have realized. It’s humus.
Benefits of humus
Mulch is easier than compost, but just as beneficial. Mulch contains only one ingredient: leaves. When applied to beds and border soils, it increases moisture retention in sandy soils, improves drainage in clay soils, regulates soil temperature, and suppresses weeds.
Compost is superior in terms of nutrients, but mulch is second to none. Supports earthworms, beneficial insects and soil microorganisms, increasing plant health and vigor.
Almost any type of leaf can be used to create leaf mold. Small leaves like beech and maple will decompose in just a few months, but large, thick leaves like oak leaves can take up to two years.
Avoid using black walnut leaves as they contain a chemical called juglone that is toxic to some plants. Although fully composted black walnut leaves are generally safe to use, this compound can remain in the leaf mold, and the leaf mold does not age as long.
How to make leaf mold
Before making leaf mulch, you need to decide where to put the mulch. You can use wire mesh to fence the leaves and load them into contractor black plastic garbage bags with lots of holes for air circulation, or you can place them in a regular compost bin.
Anyway, add the leaves lasagna-style, alternating between sprinkling with water and, if necessary, applying a light application of nitrogen fertilizer, which will speed up the process (regular lawn fertilizer will suffice).
Check the leaf pile every few weeks and water as needed to keep it lightly moist.
In spring, it should resemble humus, a black, brittle, nutrient-rich organic matter that acts as a protective layer on the forest floor.
Spread the mulch over the entire bed or border, just as you would with mulch or compost, and add the mulch to the potting mix in the container. Nutrients are released into the soil, benefiting the plants throughout the growing season.
Damiano writes for The Associated Press.
