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All about compost


Key Takeaways

  • Discarded food does not properly decompose in landfills.
  • Landfills are huge greenhouse gas polluters because of the decomposing food in them.
  • Discarded food can instead be turned into valuable compost, and landfills and incinerators won’t have to be used as much.
  • Curbside compost programs are really easy for the consumer.
  • Compost can help repair the depleted topsoil layer of the earth.

What you can do to help

  • Start your own backyard compost or sign up for a curbside collection program.
  • Ask for a community-wide organic waste collection program in your municipality.
  • Support subsidies for the creation of composting facilities and programs.
  • Pressure municipalities to ban organic waste from the trash.
  • Use locally produced compost in your home landscaping, and pressure your municipality to do so as well.

The Problem

The United States discards 40 million tons of food per year, or 30 to 40% of our food supply. 

In 2018, the last year we have on record, only 6.5% of food waste was composted; the rest was sent to landfills or incinerators, where food waste makes up 22% of municipal solid waste annually.

As a result, landfills are currently one of the largest producers of greenhouse gases in the United States, because organic waste does not properly decompose in the dark, oxygen-poor landfill environment. Instead, organic waste produces methane, an extremely potent greenhouse gas.

Burning organic waste in an incineration facility is even worse. Incinerators release greenhouse gases, particular matter, and other pollutants into the air, threatening the health of local residents. Furthermore, in heavily populated regions, municipalities often have to transport organic waste over long distances in order to access open landfills or incinerators, making the cost of disposal high.

Composting Can Help

Composting simply speeds up the natural process of decomposition (i.e., rotting) by providing the ideal conditions for bacteria to thrive.

On a large scale, it happens either outdoors in long piles called windrows or indoors in silos under controlled conditions. The end result is a nutrient-rich product that resembles soil and can be added to soil to enhance growing conditions.


  1. Reduces the need for toxic landfills and incinerators, because the volume of waste sent to such facilities would be less.
  2. Reduces greenhouse gas production in landfills and incinerators, since food waste is a primary source of those gases.
  3. Acts as a carbon sponge, drawing down carbon from the atmosphere.
  4. Replenishes our ever-dwindling nutrient-rich topsoil, and prevents soil erosion by binding soil into aggregates and increasing infiltration of water.
  5. Conserves water by absorbing rain into the ground rather than letting it run off and flow into storm water drains.
  6. Promotes healthier plant growth through improving the biological, chemical, and structural health of soils.
  7. Replaces chemical fertilizers, which produce nitrous oxide — a greenhouse gas that is much more potent than carbon dioxide.


Ways to Compost
Backyard and Community Composting 

Composting programs at schools, in community gardens, and in backyards typically involve plant waste collected in appropriate containers and are the responsibility of interested individuals. Through the right combination of “brown” and “green” ingredients, physical mixing, and time, you can soon have usable compost for your own garden.

Residential Pickup

Many municipalities across the country provide curbside organic waste collection of all types, not just plant waste. Here in Massachusetts, only one town (Hamilton) has enacted mandatory composting where the garbage is only collected if a compost bin is next to it! Whereas others allow private composting companies to operate in their communities on an opt-in, fee-for-service basis. Mandatory composting is a key tenet of an effective zero waste plan for any municipality.

Commercial Waste 

In Massachusetts, any entity that produces more than 1/2 ton of food waste per week is not allowed to dispose of it in the trash. In order to achieve the full benefits of composting, pressure will need to be put on the DEP to eventually ban any amount of commercial (and residential) organic waste from entering the trash.

Row of Recycling Bins

Organic Waste Policies


  • A number of municipalities have ordinances that require residents and businesses to separate organic waste from their trash and that fine residents who do not comply.


  • Two states (CA,VT) have passed legislation banning ALL organics from the trash.
  • Seven states (CT, MA, MD, NJ, NY, RI, and VT) have passed legislation banning the disposal of large amounts of commercial food waste and vegetative materials. Four of those states (CT, MA, RI, and VT) also have laws requiring commercial waste to be diverted from landfills to composting or anaerobic digestion facilities. Two states (MA, and WA) have regulations requiring jurisdictions to procure compost, mulch, and biogas from state and municipal recycling facilities.


  • In 2021, several Congressional representatives introduced a bill entitled the Cultivating Organic Matter through the Promotion of Sustainable Techniques (COMPOST) Act, which would designate composting as a conservation practice for all U.S. Department of Agriculture conservation programs. This bill would authorize funding for large- and small-scale projects to expand the nation’s composting infrastructure.

Deep Dive

Written by the Zero Waste Team of Brookline Mothers Out Front