To promote the decomposition of your leaves and grass clippings, combine them to create a compost pile. A properly cared for compost pile heats up, which accelerates the decomposition process, compared to a pile of damp leaves or grass clippings left unattended and vulnerable to rain or excessive heat. When you decompose your leaves and grass clippings in a compost pile, the debris transforms into a rich soil amendment for your garden.
Where you put your leaves and grass clippings to decompose plays a role in the speed in which they break down. Select a level area of dirt, away from buildings,and place the garden debris directly on the dirt. Avoid areas that experience water runoff, such as a location subject to flooding. Don't place the pile under a tree, or in an area where your pets have easy access. It is a good idea to be near a garden hose, as you will need to moisten the pile occasionally.
After moving the grass clippings and leaves to the compost area, make a pile about five-inches high and 5-feet by 5-feet wide. Sprinkle a cup of 10-10-10 fertilizer over the pile, and then add several inches of regular garden soil to the top of the pile. If you have more leaves and grass clippings, add more layers, yet remember to add the same amount of fertilizer and soil after each 5-inch layer. Decomposing involves microorganisms and bacteria feeding on the materials. Adding the soil and fertilizer creates a better environment for the process.
To decompose quickly the pile needs to be slightly moist and not allowed to completely dry out. It should be the moistness of a wrung-out sponge. Keep the pile slightly moist by sprinkling with a garden hose. Cover the pile with a tarp when it rains, to avoid getting the pile muddy. Adverse weather conditions, such as extreme heat and wind, can disrupt the balance of the compost pile, slowing or disrupting the decomposition process.
The compost pile also requires circulation to keep it heated up and breaking down the material. To circulate the pile, turn it once a week or so with a pitchfork. After about two weeks, the pile should reach the ideal temperature to decompose rapidly, which is between 110 to 160 degrees Fahrenheit. Purchase a thermometer at the garden center and check the temperature periodically. If the pile drops below 110 degrees Fahrenheit, it needs to be turned. If the pile cools off, or dries out, the decomposition process slows down.