Tree Facts: What to do with your tree leaves

Farm Forum

There are an abundance of tree leaves for homeowners to deal with this fall. Homeowners will either dispose of them or utilize them around their home and property. Options for using leaves at home include: spreading them as mulch around trees, shrubs, working them into your garden or planting beds, adding them to your compost pile and leaving some of them where they fall.

Tree leaves are excellent mulch for around trees, shrubs and flowers. They help retard weed growth, retain soil moisture, lower soil temperatures in the summer, and protect against severe temperature fluctuations during the winter that can cause injury to plants. Leaves slowly decompose, adding their nutrients to the soil and improving soil structure.

Leaves are an excellent addition to your compost pile. Shredding is not necessary but if done speeds up decomposition. Leaves are difficult to compost alone and need the addition of fertilizer, grass clippings or materials high in nitrogen. If you have room, you can save leaves to mix with green materials next summer. Normally grass clippings should be left on the lawn, but for those times when you need to collect clippings, it is useful to have leaves to mix with the grass for better composting results.

If you plan to allow tree leaves to remain on the lawn, be sure to spread out areas of leaves where they are too thick. Blades of grass should still be visible through the leaves and shredding them by making several passes with your lawn mower will make them ideal for your lawn. It does not take a very heavy layer of leaves to smother the grass, causing partial die-back, or making it more susceptible to diseases. It is often necessary to remove at least some of the fallen leaves from the lawn.

Leaves from trees with leaf diseases such as apple scab, anthracnose, or leaf spot should be removed or destroyed to prevent over-wintering of the disease organisms and re-infection of new leaves next year. Oak leaves decompose more slowly than other types of leaves and it is best to use them for mulch or compost. In fact, their slower rate of decomposition makes them well suited for use as mulch.

The decision to shred or not shred leaves for composting or mulching is a matter of personal preference and is related to the homeowner’s willingness to spend money for the purchase or rental of appropriate equipment and their ability to perform physical labor. Large volumes of leaves require use of a shredder/chipper and smaller volumes of leaves can be handled by using a lawn mower to chop leaves. Most unmodified rotary mowers will at least partially shred leaves. Use of a mulching blade may improve results.

My source for this news release was the University of Minnesota Extension Service. If you would like more information about “What to do with your tree leaves,” contact Bob Drown @605-244-5222 Extension 109 or by e-mail at