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Leaf Mulch – Improve Soil, Block Weeds & Protect Plants

Leaf Mulch – Improve Soil, Block Weeds & Protect Plants

Have you ever thought about more effective methods for utilizing the leaves you gather from your lawn?

If burning the leaves seems to you like a waste of some valuable organic materials, you’re absolutely right. You can compost the leaves to make natural fertilizer or use them in other ways throughout your yard.

Can you use leaves as mulch? Leaves are excellent to use as mulch. Flower beds, shrubs, vegetable gardens, and trees can all benefit from a few inches of leaves to suppress weeds, improve the soil’s water retention, and provide nutrients. Also, leaf mulch insulates the roots of the plants against sudden changes in weather.

Leaf mulch is a large topic, but I’ll provide comprehensive coverage below. Read on to find out all you need to know about using leaf mulch, its benefits, and whether or not it’s better than wood mulch.

Are Leaves a Good Mulch?

You can use a lot of organic materials as mulch. Pine needles, sawdust, chipped bark, and cut grass are good candidates.

Shredded leaves make a great mulch since they decompose and break down in the soil much faster than other types. Decomposed leaves release nutrients in the soil that readily absorbed by the roots.

Since leaves are a free resource in your yard, you should never run out of leaf mulch.

Does Leaf Mulch Improve Soil?

Leaf mulch has a great impact on the soil. The thick layer of leaf mulch prevents moisture from evaporating too quickly.

When the leaves break down, they enrich the soil and make it more fertile. Mulching can also prevent soil erosion.

Moreover, the shredded leaves can improve soil aeration and prevent the soil from getting compact.

Does Leaf Mulch Stop Weeds?

If you have a weed infestation in your garden, leaf mulch can be more effective and environmentally friendly than using herbicides.

Since weeds need air and light to survive, a thick layer of leaf mulch can deprive the undesirable vegetation of both.

The mulch will smother the weeds and kill them before the shredded leaves themselves break down.

As long as you keep refreshing your mulch and provide a deep enough layer, no weeds will grow around your vegetables, flowers, or shrubs.

Leaf Mulch Benefits

The benefits of leaf mulch go beyond killing weeds effectively and preventing them from suffocating your plants.

Leaf mulch improves the texture of the soil by improving aeration and water retention. It also adds valuable nutrients to the soil, which saves on fertilizers.

Mulch also regulates the temperature of the soil both in the summer and winter months. The shredded leaves before decomposition can be too acidic a medium for some pests to live or lay their eggs.

Disadvantages of Mulching

Mulching isn’t the ideal solution for every situation. Some insects will hide in the mulch layer, especially before the leaves start to decompose.

Using too much mulch can be bad for the plants. The thick layer of mulch will overheat the soil, which can damage the roots and cause the plants to die.

If the soil is already too acidic, the shredded leaves can decrease the pH even further. However, once the leaves decompose, their pH rises to neutral levels. 

Does Mulch Attract Termites? Other Pests?

Mulch can be a good place for termites and pests to hide. That said, mulch itself doesn’t attract pests from outside of your garden.

The shredded leaves don’t offer any source of sustenance to the pests. They’re just a convenient place to hide.

If you notice pests or termites in or around the mulched area, use less mulch to allow sunlight to penetrate the shredded leaves and chase the pests away.

Leaf Mulch vs. Wood Mulch

If you’re weighing whether to use leaf mulch or wood mulch in your garden, you need to consider the type of plants you want to mulch.

If you’re mulching a garden vegetable or a bed of annual flowering plants, then leaf mulch will do a better job. The shredded leaves decompose faster and release their nutrients in a short time into the soil. 

Wood mulch is more suitable for perennials, evergreen shrubs, and trees. It takes longer to break down, but it also lasts longer in the soil.

It slowly feeds the perennials for months on end before you have to refresh the mulch. 

What Is the Difference Between Leaf Mulch and Leaf Mold?

Leaf mulch is shredded leaves that you spread over the soil. Leaf mold is decomposed leaves that fungi has broken down. You can use leaf mold as a substitute for compost.

It doesn’t have the same nutrients as compost since it lacks green elements. Unlike compost, which is decomposed by bacteria, fungi break down the organic materials in leaf mold.

Leaf mulch takes time to decompose and release its nutrients into the soil.

Is Leaf Mulch Good for the Winter?

Leaf mulch is light, fluffy, and insulating. It protects the roots of the plants in the winter from freezing.

However, if you want to keep your plants well protected and fed at the same time during the long winter months, you should use either wood chips or pine bark.

Both of these take longer to break down than leaf mulch, which offers longer protection to the roots of the plants.

Should You Remove Leaf Mulch in Spring?

You shouldn’t be too hasty to remove leaf mulch in the spring. You should wait for the temperature to rise above 45℉ before removing the mulch.

That will keep the plants protected and prevent damage to the flowers.

At the same time, if you delay removing the leaf mulch after the weather has warmed up, that could raise the soil temperature and suffocate the plants. 

How Long Does It Take Leaves To Decompose?

If left on its own, a fallen leaf would take anywhere from 6 to 12 months to decompose. In a compost pile, the same leaf will take between 3 to 6 months to break down.

However, leaf mulch usually decomposes at a fast rate due to the high temperature and humidity levels in the layer of leaf mulch.

Do You Have to Shred Leaves for Mulch?

In general, shredded leaves break down faster than whole leaves in a layer of mulch.

Moreover, shredded leaves offer less space for insects to hide and totally smother weeds by cutting off the air supply and sunlight.

Unlike whole leaves, shredded leaves take up less space to store, so it’s always a good idea to shred the leaves before storing them or using them as mulch.

Can You Use Whole Leaves as Mulch?

Colorful autumn leaves being raked.

Whole leaves can be used as mulch, but they will take a longer time to break down and release their nutrients into the soil.

Additionally, they offer more space for pests to hide and might not improve water retention in the soil the same way as shredded leaves.

How To Shred Leaves for Mulch

The best way to shred leaves for mulch is to let them dry out first. Don’t try to shred leaves immediately after rainfall since wet leaves are harder to shred.

When they’re totally dry, run them through a lawnmower to decimate the leaves and make them ready for mulching.

What Leaves Are Not Good for Mulch?

Not all leaves are good for mulching. Leaves that are low in nitrogen and high in lignin are not good to mulch with. These include leaves of oak, sweet chestnut, holly, and beech trees.

Other leaves to avoid are those that have high concentrations of natural herbicides that could poison the plants. Avoid leaves of eucalyptus and black walnut for both mulching and composting.

How Deep Should Leaf Mulch Be?

For most garden flowers, veggies, trees, and shrubs, you should use a layer of leaf mulch between 2 and 3 inches thick.

If the mulch is less than 2 inches deep, it will not do a good job regulating the temperature of the soil, killing weeds, and improving water retention.

If it’s thicker than 3 inches, it can increase the soil temperature and damage the roots of the plants.

How Much Leaf Mulch Is Too Much?

If the leaf mulch is thicker than 3 inches, it can have adverse effects on the plants and the soil. It could deplete nitrogen in the soil and retain the water for far too long, which could lead to root rot. 

Using Leaves as Mulch in a Vegetable Garden

When using leaves as mulch in a vegetable garden, make sure the leaf mulch doesn’t touch the base of the vegetable plants.

Spread the leaves in layers between 2 to 3 inches thick. When the mulch breaks down, refresh it with a new layer.

Where To Buy Leaf Mulch

If you have a deciduous tree or shrub in your garden, you can use the fallen leaves as leaf mulch. The same applies to the annual plants that grow in your garden.

Otherwise, you can buy leaf mulch from the local nursery or from shops online.

Conclusion

Leaf mulch is a valuable source of rich nutrients for the plants growing in your garden.

Apply a 2-3 inch layer of mulch to suppress weeds, prevent soil compaction, add nutrients, and regulate the soil temperature.