"Over those three decades, San Francisco's composting (has turned) 5.8 trillion pounds of material into compost, kept out of landfills, turned into a beautiful soil amendment that goes on to local farms," says Robert Reed, spokesperson from Recology, the Bay Area waste management company behind the curbside composting program that is now marking 30 years.
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According to Reed, the curbside composting model has since been replicated across the United States and internationally, with other agencies visiting Recology's facilities to learn the approach.
"And they continue to come: the Brazilians are coming, or a group coming from Mongolia. We helped inspire a national law in France, requiring every municipality in the country to make composting convenient to their residents and their businesses," Reed says.
Full Circle Farm in Gilroy is one such farm that uses the compost produced by Recology.
The small farm prioritizes individual plants over long rows of plowed fields, relying heavily on compost to retain moisture and protect roots during hot summer months.
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Owner Zoe Davis says compost is central to the farm's approach because the soil is not tilled and planting beds are reused year after year.
"Because we're not tilling, we kind of have these stable beds that, we're using, year after year," Davis says. "So, we're taking nutrients out of the system that we need to bring organic matter back in and bring nutrients back into the soil."
Davis says composting connects consumers and growers in a shared cycle.
"The name of our farm is Full Circle Farm. And we chose this name because that's the whole concept in micro and macro that we are part of the community. We are providing food to the community and the community is providing for us with their business and with their green waste," she says.
The program at Recology turns household kitchen scraps such as broccoli stems, eggshells, banana peels and coffee grounds into material used by local farms instead of sending it to landfills.
The method, which Reed says has been refined over decades, involves multiple steps and can take several months to complete as raw scraps are sorted, sifted and filtered into dark, organic compost suitable for farms.
Recology says curbside composting programs are now operating in roughly 400 cities across the country.