Leaf mulch or leaf mold is by far my current favorite of our mulches right now. It is a great way to recycle the fallen leaves from our local trees and turn them into nutrient-rich mulch that benefits a garden.
Leaf Mulch has all of the traditional benefits of mulch, but it also adds nutrients to the soil over time as an organic mulch. I also love that when I make leaf mulch at home, I don’t have to bag my leaves or buy as much mulch, saving me time and money (more below!)
While I had been familiar with leaf mulch for a while, I never had a chance to use it in my garden until this year. Indeed, professional landscapers (and some in-the-know gardeners) have been using leaf mulch for many years, but it now seems to be getting a lot of traction as its own type of mulch, and rightfully so!
I love that a leaf mulch holds its color for a long time. Dyed mulches are okay at this, but as I’ve described in an earlier blog post, dyed mulches aren't good for a garden. Natural mulches are a great option too, although they lose their natural dark brown color a little faster than leaf mulch (please see, what's the best kind of mulch?).
For our native plant garden at our composting facility in Manassas, VA, I like that the natural double mulch settles into a lighter color. This looks a little more natural to me and helps reflect the hot summer heat (protecting the soil and plant roots below).
At my home in the greater Washington DC / Northern VA area, however, I want the darker brown of the leaf mulch to stay as long as possible. In the fall, I create my own leaf mulch at home (below) and it’s a lighter color. In the spring, I get my leaf mulch from my work in Prince William County, and it’s a beautiful dark brown. Usually, by the time the color starts to fade slightly in the fall, I’m going to replace the mulch anyway.
Making leaf mulch (How to make leaf mulch)
We make leaf mulch at our composting facility by grinding up (deciduous tree) leaves and then bringing them through a natural curing process. We heat up the leaves to kill any weed seeds in the pile, ensure the pile has water, and allow it to darken over time. The leaves are then screened so that the mulch is a relatively consistent size. Because the leaves are so thin, this darkening and aging process allows the dark brown to move throughout the full leaf (of the leaf mulch).
It is really easy to make a leaf mold at home. Who doesn’t love free, easy, and less overall work? Here are some steps to making an easy leaf mulch:
Gather leaves. Rake the fallen leaves in the fall from your yard, or get leaves from your neighbors or public areas like a park.
Shred the leaves. A leaf shredder or lawn mower can shred leaves quickly and relatively easily. I use my leaf shredder and then empty the bag right onto my garden bed. I don’t take the remaining steps! Rather, I let them age in place on my garden since I know where the leaves have come from. (I don't need to "cure" it to kill weed seeds in this case.)
Pile the leaves. Put the shredded leaves into a compost bin, a wire cage, or a simple pile on the ground. While I prefer not to use plastic, I’ve heard some people have great luck putting them in large, black contractor bags and aging the leaf mold this way. If you’re making a pile on your ground, try to make it three feet wide by three feet tall so that it can generate enough heat to decompose.
Wet the leaves. Spray the leaves with a garden hose or watering can. This will give moisture to the pile and help speed up the leaf’s decomposition. The water helps grow the healthy microorganisms that will break down the leaves.
Turn the pile. Use a garden fork or shovel to turn the pile every three to four weeks. This helps aerate the leaves and gives the leaves on the outside of the pile a chance to get the heat from the inside of the pile so there is even decomposition.
Wait. It can take three to twelve months for the leaves to fully decompose. Again, I stop at step 2, I’m happy to let nature take its course in my garden over the winter.
Benefits of a leaf mulch or mold
Leaf mulch not only adds a beautiful color and smooth texture appearance to a garden, it has a variety of really great benefits for my garden soil.
Soil amendment. Leaf mulch, as a soil conditioner, helps improve soil structure, increase soil nutrients, and retain moisture. It decomposes quickly on a garden, so it is important to add it in the spring and fall. Out of all of the mulches that I know of, leaf mulch is the best at enriching garden soil.
Weed suppression. Leaf mulch helps suppress weed growth because it either stops the weed seeds from reaching the soil to germinate or, if the weed seed makes it to the soil, it blocks the sunlight so that the weed doesn’t grow. Because leaf mulch is a finer material type, it’s not as good at stopping weeds as other mulches.
Erosion control. Leaf mulch provides a little help in preventing erosion because it is a protective layer over the soil, reducing the impact of rain and wind on the garden soil. However, if you have sloping or notably uneven terrain, leaf mulch may not work as well as other mulch. Because the leaves are relatively light, water can more easily lift the leaf mold and carry it away. I have given some recommendations for reducing soil erosion in an earlier blog post.
Moisture retention. Leaf mulch helps retain moisture in the soil and this is especially helpful in our hot Northern Virginia summers. The mulch acts as a barrier, reducing the amount of water that is lost from evaporation.
Aesthetics. I love how flat a leaf mulch lays against my garden soil (so I had to mention it again :) ). It’s a natural, earthy look that complements the garden style that I have in the front of my house.
Using leaf mulch
I apply a leaf mold just like any other mulch (how to use mulch), but I think spreading two to three inches is enough. While other mulches might be able to go up to four inches, I would stay on the lower end of the range since this is a finer mulch.
I've loved using a leaf mulch this year and, if you haven't given this a try yet, look forward to hearing about your experiences below!
About Freestate Farms' Compost & Mulch Facility
Freestate Farms makes premium landscaping products—compost, topsoil, and mulch—by recycling food and yard waste in Manassas, VA. Our composts, topsoil, and mulches are specially designed to increase the health and productivity of local soils, and with our focus on sustainable practices, this lets the environment and your garden Grow Good, together. We sell bulk compost, bagged compost, bulk natural mulches, bulk dyed mulches, bagged dyed mulches, and bulk topsoil.