Take Advantage Of Free Fertilizer...
Use Your Leaves!

Barb Mrgich
Adams County Master Gardener

Autumn is just about upon us, and you know the other word for the season -- Fall. Why? Because the leaves will soon be falling all around us. Many people think of falling leaves as something that must be raked up and thrown away, but leaves are intended by nature to be a natural fertilizer and protective cover for the earth.

Go into a forest where no one ever rakes up the leaves, and dig down a few inches. Have you ever seen such dark, fertile soil? You don't have to be a gardener to know that if you were a plant you would rather live in this soil than in the stuff most of us have in our yards. The difference, of course, is the leaves.

Leaves are full of nutrition that nourish the organisms that live in the soil. These organisms in turn help produce healthier roots on your plants, including your lawn grass. You may be saying, "I can't just allow leaves to pile up on my grass. It will kill the grass." You are probably correct, but that doesn't mean bagging them and sending them to the landfill is the answer.

Try a new approach this year. When the leaves start to fall this autumn, continue to mow the grass as usual. Mow right over the leaves, letting them scatter over the grass. You can mow over leaves that are one foot deep, and your grass will be happy, but it's better to mow often before they pile up, so you don't clog the mower. This is much less work than raking and stuffing them into plastic bags.

The secret to healthy soil in your garden or lawn is feeding the billions of living organisms in addition to the earthworms that live in that soil. The best way to do that is by adding organics to the soil. Chemical fertilizers are artificial. True, the plants can't tell the difference between natural and artificial nutrients, but those living microorganisms in the soil can. By feeding your soil instead of your plants, the soil becomes healthier, the plants develop better, deeper roots, and they, in turn, become healthier and more self-sufficient.

A lawn on a strictly chemical diet may look green and lush as long as you continue to water and fertilizer it. If you stop regular feedings or watering, the grass will die off quickly because it has shallow roots and no reserves. Chemical fertilizer supplies nutrients to the plants, but the high salt content will eventually kill the microorganisms, leaving you with dead soil! In a lawn fed organically, the grass will have deeper and healthier roots, and will be able to withstand periods of stress and drought.

Many people think that if they mow their grass without bagging, they will be creating thatch, but this isn’t true. Grass clippings are full of nitrogen which the grass needs. In autumn, when the leaves start to fall, you should keep mowing, mixing the grass clippings with the leaves.

This same idea for feeding the soil applies to your garden. The easiest way to make good garden soil is to mix grass clippings with chopped leaves and apply them to your garden beds as mulch each fall. It will supply nutrition to the garden soil, help retain moisture, and provide a breeding ground for those good microorganisms. In your vegetable garden, apply a thick layer of leaves and grass in the fall, and you can eliminate the need to till in the spring. This will save you work, eliminate much of your weed problem, and improve the over-all health of your soil. Tilling chops up your earthworms and microorganisms, and it exposes buried weed seeds to the light and oxygen they need to germinate.

In a perennial garden, a layer of leaves and clippings will not only nourish the soil, it will insulate the ground, preventing heaving and protecting the crowns of your plants. There is one note of caution to all this: if your lawn has recently been treated with a broadleaf herbicide, you don't want to be spreading that grass in your perennial garden!

As valuable as leaves and grass clippings are to us in our yards, they are a huge problem in landfills. We hear constantly that landfills are running out of room and that billions of dollars are spent each year to handle the situation. Did you know that according to the EPA, as much as 50% of that waste comes from plant debris...namely grass clippings and leaves! This is one environmental problem to which we each have the opportunity to contribute to the solution.

Read other articles on ecological gardening & native plants

Read other fall related gardening articles

Read other articles by Barbara Mrgich