Leaves can be added to the compost heap but it is best to shred them first. This can be done by mowing over them on the lawn and collecting them in the mower bag. They can also be added directly into the planters. Incorporate two- to three-inches of shredded leaves to the soil at a time. This can be repeated until the leaves are gone or the soil is frozen and cannot be worked. Shredded leaves can be used as mulch around trees, shrubs and perennials as well.
The shredded leaves can be left on the lawn if they are not too dense. If you can still see the lawn through the leaves overtop it should be safe to use this option. As you mow, the leaf pieces will fall in between the blades of grass and eventually break down into the soil. It may require multiple passes with the lawn mower to get the leaf size small enough. It is also necessary to mow frequently to keep up with the leaf drop. Some benefits of this approach have been reported in research. Leaf mulch incorporated into lawns can help prevent weeds from germinating between grass plants. Leaf mulch has not been shown to negatively effect on turf quality, color or soil pH.
If you are incorporating leaves into a cool-season lawn, it makes sense to be on a fall nitrogen fertilization program and core-aerate in the fall as well. You can mow leaves into a warm-season lawn, but wait to fertilize and core-aerate until late May or early June. (Cynthia Domenghini)