We all rake leaves in the fall, but this year, resist the urge to bag and dispose of these gifts from nature. Autumn foliage adds nitrogen and phosphorous to the soil, provides food for soil microbes and increases the soil’s tilth and moisture retention.
Leaf composting in windrows at the Rodale Institute, Kutztown, Penn., makes humus-like leaf mold to enrich Rodale’s experimental gardens.
Top: Amending this newly expanded bed edge with decomposing leaves and compost adds organic material for microbes and aids moisture retention.
Bottom: A thick layer of oak leaves protected this fig tree’s roots and lower trunk through winter.
Walking through a woodland can be like stepping onto a soft sponge. The soil sinks underfoot and then springs up after your shoe lifts off. Dig a heel in the dark, rich earth. It is loose, light and airy, yet moist. This humus from the forest foliage is full of microbes. It feeds the trillium and native orchids, the oak and white pine, the blueberry bushes and viburnum.
We can make similar magic in our gardens — with little effort and some strategy. Autumn leaves are nature’s gift, compost-in-the-making for our landscape’s benefit. Leaves decay into leaf mold — black humus alive with earthworms, packed with nutrients and beneficial bacteria and fungi (living aerators and fertilizer makers) and water-holding material.
The Rodale Institute has an impressive composting process to produce leaf mold to improve soil texture and water-retention in their experimental gardens. They mechanically turn leaves piled in huge windrows. This periodic aeration encourages fast, complete decomposition.
We gardeners can improvise and get the good stuff, too. Using even partially decomposed leaves reaps environmental, financial and horticultural benefits.
Resist Blowing, Bagging and Disposing
Look with new eyes at recycling leaves to enhance your landscape and enrich your soil. Here are some possibilities:
- Have a tenacious weed patch you’d like to turn into a garden? Heap piles of leaves there after you remove the weeds this autumn. Come spring, dig or till the leaves into the soil and plant. This also works for weedy slopes, as the leaves help hold the soil in place until you install the new plants in spring.
- Want to save your leaves but not sure where to use them? Pile them someplace inconspicuous or bag them for the winter. They’ll decompose and become more compact over the winter, and then they will be ready for a spring project.
- Use raked leaves as mulch. Mulch created with leaves keeps weeds down, protects woody and perennial plants’ roots over the winter and the leaf mulch decomposes to improve soil.
- Want to make rich leaf mold? Shred your leaves, place them in a pile, then wet them and combine with a nitrogen source such as alfalfa meal, compost starter or grass clippings. Turn this pile occasionally until next gardening season.
- Eager to expand or make a new garden or shrub bed now? Remove the grass and weeds. Top this area with leaves and compost. Dig or till the soil, incorporating leaves and alfalfa meal for nitrogen. Pile on more leaves to cover the bed. Remove leaves in spots where you plant.
These beautiful spring flowers and ferns emerged from soil covered with leaves that decomposed over the winter and were turned under in a spring digging.
Last fall’s leaves were this spring’s mulch on a slope of rhododendron and hosta.
From State-by-State Gardening September/October 2011. Photography by Charlotte Kidd.
Charlotte Kidd, M. Ed. is a writer, professional gardener, garden designer, garden coach and educator at Charlotte@CharlotteKidd.net. She is also a regional editor for the National Gardening Association.