Keep America Beautiful

students using compost

COMPOSTING

Composting is a natural method for recycling organics like yard trimmings (12.1%) and food scraps (11.7%), which comprise nearly a quarter of municipal solids waste generated. 

According to the U.S. EPA, composting diverted 7.1%, or 16.9 million tons of municipal solid waste, from landfill in 2003.  Nearly half of all U.S. states now ban yard waste from landfill because it represents such a large volume and because it can be productively composted.  There are about 3,225 community composting operations nationwide.

What is Composting?

Composting is the aerobic, biological decomposition of organic materials.  Living microbes combine with oxygen to cause decomposition.  The end result is a nutrient-rich, soil-additive called "compost". Get a description of the different types of composting.

What Can Be Composted?

Nearly all organic byproducts, including food scraps, leaves, grass, yard clippings, nonrecyclable paper (paper towels, napkins, etc.), and sawdust and other wood products, can be composted.

Just over 56% (16.1 million tons) of yard trimmings were recovered for composting in 2003. This is a fourfold increase since 1990. About 2.7% of discarded food scraps were recovered in 2003. Find out more.

Using Compost

Finished compost is widely used in agriculture and horticulture (gardening), landscaping, golf course construction and highway beautification, and in creating landfill cover (the layer of soil that is placed over old landfills after they have reached capacity).

Get the tools to start composting in your community.

Types of Composting

  • Grasscycling is a form of waste minimization that involves the natural recycling of grass clippings by leaving the clippings on the lawn after mowing.
  • Backyard Composting enables residents to compost yard trimmings and other organic materials in their backyards.  When home composting, it is best to keep out meats, grease, and other materials that may attract pests.  The finished compost can be used to improve the lawn and garden.
  • Vermicomposting uses red wiggler earthworms to process food scraps and other organics into worm casting.  The worms eat over half their body weight each day.  The nutrient-rich worm castings are beneficial to plants and soil.  This method is often used inside homes and school classrooms, although there are some larger vermicomposting facilities.
  • Yard Trimmings Composting is the large-scale processing of grass, leaves, tree limbs, trunks and brush, and garden materials into finished compost.  Yard trimmings may be brought to drop-off sites or picked up at curbside and sent to municipal composting facilities.
  • Source-Separated Organics Composting Programs rely on residents, businesses, and public and private institutions to separate one or more type of organic materials and set them out separated from other recyclables and trash for collection and eventually composting.
  • Mixed Municipal Solid Waste Composting is when a commingled stream of solid waste is sorted to remove recyclable, hazardous, and noncompostable materials, and the remaining organics are composted.