Recycling, nature’s way
How to turn food scraps into fertilizer
Americans fill landfills with the equivalent of 48,000 Olympic-sized swimming pools of solid waste each year. And it’s not just dirty diapers and old tires taking up all that space; food and yard trimmings make up about 30 percent of landfill waste.
But nature has its own way of recycling, one that is bypassed when food ends up in the trash heap: the compost cycle.
Members of the Rotary Club of Madison, Wisconsin, started a composting project in 2022 that diverts food scraps from their weekly lunch from the landfill and turns them into fertilizer for a community garden affiliated with an elementary school.
Rotary members constructed three compost bins at the site, educating growers about which plant materials were best to include. Meanwhile, they worked with the kitchen staff at the hotel where they hold their lunch to collect food waste — think carrot shavings, pineapple rinds, onion skins, and spoiled cauliflower. The waste is transported each week to the garden, where volunteers mix the scraps into the bins.
After a few months, the finished compost is ready to use to fertilize the garden plots. “It’s great for the kids, great for the community, and great for Rotary,” says David Edinger, who spearheaded the project as co-chair of the club’s Going Green Fellowship. Here’s a closer look at how it works.
This story originally appeared in the December 2023 issue of Rotary magazine
Illustration by Clara Candelot
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1. Hotel staff save “green” materials high in nitrogen like fruit and vegetable scraps.
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2. Growers add carbon-rich “brown” materials — dry plant matter such as dead plant clippings, fallen leaves, and straw bales.
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3. Worms and microorganisms digest the organic matter, using it for growth and reproduction. Volunteers maintain the pile by keeping it damp and turning it to create air pockets, since the microbes need oxygen to survive. The work of the microbes heats the temperature to 140 degrees or higher, hot enough to kill off pathogens.
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4. Growers use the remaining dark, crumbly material as fertilizer for their gardens.
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5. Plants absorb the nutrients, helping produce more fruits and vegetables to eat.