Cold or Slow Composting
Cold or slow composting can be accomplished with nothing more than a pile grass clippings and dry leaves on the ground or in a bin. This method requires no maintenance, but it will take several months to a year or more for the pile to decompose. Cold composting works well for gardeners who lack the time to tend the compost pile at least every other day, have little yard waste, and are not in a hurry to use the compost.
Keep weeds and diseased plants out of the mix since the temperatures reached with cold composting may not be high enough to kill the weed seeds or disease-causing organisms. Add yard waste as it accumulates. Shredding or chopping speeds up the process. To easily shred material, run your lawn mower over small piles of weeds and trimmings. Cold composting has been shown to be better at suppressing soil-borne diseases than hot composting. Cold composting also leaves more undecomposed bits of material, which can be screened out if desired.
Adapted from the USDA Backyard Conservation Tip Sheet, a public-domain work of the US Government.