6 Reasons to Use Autumn Leaves as Mulch!

Autumn leaves are one of the most underappreciated resources for your garden. In this article I will show you how you can use your leaves to drastically improve soil health. Using leaves as mulch was the single biggest factor for the improvement in my garden soil.

The main benefits of using leaf mulch are:

Improve soil fertility, nutrients
Improve soil moisture retention
Prevents weeds from germinating

How to Make Leaf Mulch

To make a mulch from leaves, all you need to do is rake them up and layer them where you want a mulch. To make sure they don’t blow away, use a hose or sprinkler to water the leaves and then walk on them or run your wheelbarrow over them to crush them up a bit. If you are finding bagged leaves on the street, then simply sit or walk on the bag a bit to crush and interlock them.

Should you shred leaves?

Shredding the leaves would have several benefits in that it would decompose quicker, allow more moisture to penetrate the soil, and they are less likely to blow away. The unfortunate thing is that in shredding them you may kill insects that pupate in cocoons attached to the leaves.

After using leaf mulch in my vegetable garden for several years I have tried both shredded and whole leaves as mulch. I no longer shred leaves when I apply a leaf mulch. The mulch will last longer, meaning I will have a natural weed barrier for more of the growing season. And I have observed that my plants are just as happy whether or not they are shredded.

1 – Leaf Mulch adds organic matter to soil

Over the winter and during the next growing season the leaves will break down naturally. This will create a layer of organic matter on top of your soil. Worms will naturally transfer this layer down into your soil. This layer of organic matter will also naturally penetrate the soil over time.

A 6-12″ thick layer of shredded leaves on my vegetable garden

Organic matter will help any soil. Clay soil drains better (and digs easier) with the addition of organic matter. Sandy soil will hold moisture better with addition of organic matter.

Also, Did you know that leaves can be used to make compost (Link to our post on our easy method to compost.) Now you do.

2 – Leaf Mulch Improves Soil Fertility

Gardeners the world over have known for centuries the benefits leaf litter can have on soil fertility. Many university studies have actually quantified just how much fertility can be improved by the amount of leaves. [1] [2]

*Want to know how many nutrients and their quantities are actually in leaves? Click Here!

3 – Leaf Mulch increases moisture retention

Leaf mulch and shredded leaves will decompose and increase the amount of organic matter in soil. Research has consistently shown that organic matter increases moisture retention. Gupta & Larson developed a regression model showing positive correlation between organic matter and water content of soil [3].

4 – Leaf Mulch increases available minerals

Tree leaves transfer minerals and other nutrients to leaves during the growing season. They are able to pull these nutrients from the deep roots of the tree. At the end of the growing season, after the leaves fall, they return the minerals to the ground through decomposition.

Beneath the layer of leaf mulch is about 2-3″ of black loam, then into the clay. And note the worm in the clay, thereby spreading organic matter and reducing compaction.

You can naturally add these essential minerals to your soil by letting shredded leaves decompose in your garden.

5 – Leaf Mulch will reduce and prevent weeds the following year

By creating a new layer of organic matter on top of your soil via decomposing leaves, you create a barrier. Well, that barrier will prevent sunlight from reaching weed seeds, thus preventing weed germination.

Since I started using leaf mulch in my garden, I’ve had far fewer weeds. My soil used to be overrun with all types of clover and grasses. But I was amazed just how quickly the leaf mulch helped prevent weeds from even germinating.

6 – Leaf Mulch is FREE

You can get leaves for free from your own yard. You can also just take them from the street! In my neighborhood (and probably yours too) people rake their Autumn leaves and leave them bagged along the curb. They are essentially throwing away free fertilizer/compost material!

So, turn your neighbors loss into your gain by swiping their ‘trash’ aka leaves!

Should you till the leaves into the soil?

NO! Don’t till the leaves into the soil. It is not necessary. If the leaves decompose within the soil they will consume nitrogen, thus depriving your vegetable plants of a key nutrient. Just leave them on top of the soil, and their nutrients will do their thing, and be available for your veggies!

Want to learn how to use leaf mulch to get a MASSIVE soil fertility improvement? You can see our year over year results in the video below!