Municipal composting programs turn trash into ‘black gold’ that advances food security and social justice

Almost overnight, the COVID-19 pandemic has changed many Americans’ relationship with food. To ease the stress of safely grocery shopping and ensure food security, many people are replanting “victory gardens.” This tradition goes back to previous generations who cultivated home gardens during both world wars.

Interest was high even before the pandemic. In 2014, the National Gardening Association reported that 42 million U.S. households – about 1 in 3 – grew some type of foodboth at home and community gardens.

But home gardening isn’t always effortless. Penniless soil quality makes it tough to grow vegetables and produce food. And many gardeners, especially in lower-income communities, don’t have access to resources that can improve soil quality.

We are scientists who have analyzed the power of microbes in environments where they occur: forest soils and permafrost, built environmentAND digestive system and agricultural soilsIn our view, the time has come for major public investment in a well-known gardening resource: compost.

Microbes make compost by breaking down organic matter, such as food scraps. Compost improves soil health so much that it is often called “black gold.” Enormous-scale municipal composting is a public resource that can reduce food waste, cut greenhouse gas emissions and promote better stewardship of our most precious natural resource: soil.

How Compost Nourishes the Soil

Vigorous soils are a living mix of minerals, microbes, organic matter, water, and air. Unhealthy soils may have fewer microbes or less organic matter. This makes them less vigorous and less helpful to plants. Penniless soils have trouble holding water and are unable to break down organic matter into usable building blocks for novel growth.

To make degraded soils healthier, microbes need to be fed. They need novel organic matter—plant or animal tissue—that they can break down and recycle.

In vigorous soil, some of that food comes from growing plants, which capture carbon from sunlight and pump almost half of it, as sugars, into the soil. In return, the microbes provide other nutrients that plants can’t get on their own.

Soil microbes also feed on venerable organic matter, such as leaf litter and dead roots. And novel biochemical analyses suggest that when these microbes die, they themselves become part of the soil organic matter.

To make good compost, you mix green plant waste, such as vegetable peelings, garden mulch, or straw, with brown organic matter, such as soil or manure. Then, over a period of weeks or months, microbes turn the mixture into compost that looks like soil.

This process generates heat as microbes break down chemical bonds in plant matter, releasing energy. Composters can reach internal temperatures of up to 170 degrees Fahrenheit. The heat kills potential microbial pathogens that may be carried along with manure inputs.

When gardeners add compost to the soil, the organic matter in the compost acts like a sponge for water. It is also a reservoir of nitrogen, phosphorus, and other micronutrients that plants need to grow.

Access to compost is a matter of equity

If compost is such a wonderful resource, why don’t more people make their own? In many cases, vigorous soil is a luxury. It takes time to start a compost pile, then continue with maintenance—adding browns and greens at appropriate intervals, watering the pile, and turning it weekly in summer or monthly in winter.

Composting also requires tools and building materials that not every novice gardener can afford. It requires access to space and a affable regulatory environment that allows residents to create compost piles that can emit odors and attract pests if not managed properly.

Factors like these are driving interest in municipal composting programs, where a community collects and recycles residents’ organic materials. These programs typically accept food and yard waste from restaurants, schools, businesses, and local residents and create large-scale, professionally managed composting plant.

Municipal composting saves communities money because preventing food waste from going to landfill. It also promotes sustainable development by reducing methane emissionsa powerful greenhouse gas produced in landfills when waste decomposes without oxygen. And combining many different waste sources improves the decomposition of organic materials and generates more nutritious compost.

Many city programs allocate a certain amount of compost to participants in exchange for the waste they deliver. Some offer Pickup and delivery.

Expanding composting programs

We encourage those with the time and resources to do so. try home composting. However, creating and supporting municipal composting is necessary to significantly reduce greenhouse gas emissions from food waste and enhance access to vigorous soil.

Composting programs are sometimes available through local community gardens or farms. Many private companies operate local compost collection services.

Among U.S. cities, leaders in promoting municipal-scale composting services include: San Francisco, Seattleand smaller cities such as Burlington, VermontThese programs rely on local ordinances that either offer incentives or require restaurants and other vast sources of food waste to compost their food waste instead of sending it to landfills.

Urban composting needs consumer support to attract and retain funding and other resources. Demand for land, especially in urban areas, can lead city governments to sell underfunded or underutilized community spaces for commercial apply – especially if local neighborhoods lack of social capital to be able to apply for oneself.

Promoting local food production and waste recycling through composting provides many benefitsIt creates jobs, increases access to vigorous fruits and vegetables, improves the local environment – ​​especially the soil – and helps mitigate climate change. Best of all, investing in local agriculture helps boost the local economy, especially for those who need it most:people seeking better access to protected and nutritious food.

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