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Community Compost Thrives in San Diego

By Jen Boynton

Fresh compost is a beautiful thing. It's the color of ground coffee and the smell of earth after a fresh rain. This soil supplement is gold for gardeners looking for thriving veggie plants. And it all comes from waste -- things like carrot tops, cantaloupe rinds, stale bread -- that most restaurant staff and diners would toss in the trash without a second thought.

Food2Soil, a micro-enterprise founded and supported by Inika Small Earth, exists to strengthen these local streams and "resource the local food web," Sarah Boltwala-Mesina, executive director of Inika Small Earth, explained.

Food2Soil allows community gardeners to benefit from the food waste streams of local restaurants. Here's how it works:

Food2Soil contracts with a local restaurant to pick up buckets of pre-consumer food waste like kitchen scraps (no meat or dairy here). A so-called 'compost technician' picks up the buckets and delivers them to a local community garden where s/he turns the compost, monitors the temperature, and balances green and brown waste to ensure a beautiful, high-quality soil for the community gardeners to use in their planting boxes.

Boltwala-Mesina told TriplePundit she prefers to think of these technicians as "soil growers" rather than "waste pickers." And her goal is to "bring professionalism to the world of composting and community gardens."

The group focuses on pre-consumer kitchen waste in order to keep the compost quality extremely high. "We pick the waste streams that have value for the community and let the others go," Boltwala-Mesina explained.

This careful attention to inputs is wise for any rookie composter who hopes to create usable soil. While composting can be as straightforward as piling some yard waste in a corner of the lawn, it's a bit more difficult to produce the soil amendment that gardeners and famers crave.

Underneath the surface of your average active compost pile, the organic and chemical reactions are quite complex. As the U.S. Department of Agriculture explains: "An incredible diversity of organisms make up the soil food web. They range in size from the tiniest one-celled bacteria, algae, fungi, and protozoa, to the more complex nematodes and micro-arthropods, to the visible earthworms, insects, small vertebrates, and plants." Setting the right temperature and ratio of brown to green waste are key to getting the right mix of organisms to thrive.

Thus, Food2Soil's soil growers rightly take their jobs extremely seriously. We spoke to one, Elicia, who has a master composter certification and oversees composting for the San Diego Zoo when she's not working with Food2Soil. She calls Food2Soil "super well-run" and loves the community engagement aspect of the organization's mission.

Indeed community value is at the core of Food2Soil's raison d'etre. The group wants to demonstrate that composting at the ultra-local level is a vibrant model that other groups around the country can emulate. Its goal is most assuredly not to replace commercial composting initiatives, but rather to augment them with an option that provides value for local gardeners and other community members. Ultimately, this local investment could even lead to more green jobs and local economic activity.

This vision of a local food web hinges on the participation of restaurants, which both fund the service ($20 per pick-up) and commit to sorting in the kitchen, which can be a challenge when it comes to educating a large staff about how to divert usable material from the rest of the waste stream.

Food2Soil now has five restaurant clients, each paired with a community garden. The largest by far is the Marriott Resort and Spa at Coronado Island.

The compost program at the Marriott is spearheaded by Executive Chef Michael Poompan, who heard about Food2Soil from a fellow chef and was eager to get involved.

The compost program at the Marriott consists of five large compost boxes with room to grow if needed. Poompan plans to use the resultant soil to plant an herb garden to bring free fresh herbs into his fine-dining kitchen.

The kitchen's compost stream is now full of fruit waste from the hotel's daily breakfast buffet, so the experts at Food2Soil offer advice on other materials to add to produce a balanced final product. In order to get the green light for the project, Poompan had to demonstrate that the compost program could result in real financial savings, in the form of avoided trash tipping fees.

"Measurement was hard," he joked, explaining his team's reluctance to separate compostables and weigh them every day, only to combine them again. But the experiment paid off, not only at his local hotel, but also up and down the chain.

The Marriott's project goes far beyond the walls of the luxury resort in Coronado -- it struck the interest of Marriott's corporate headquarters. They are treating the project as a pilot which, if successful, could be rolled out at Marriotts all around the world. The value associated with savings on food disposal costs, combined with the benefit of growing local produce for the kitchens, was too good to pass up.

Image credits Miriam Swaffer for TriplePundit 

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Jen Boynton is the former Editor-in-Chief of TriplePundit. She has an MBA in Sustainable Management from the Presidio Graduate School and has helped organizations including SAP, PwC and Fair Trade USA with their sustainability communications messaging. She is based in San Diego, California. When she's not at work, she volunteers as a CASA (court appointed special advocate) for children in the foster care system. She enjoys losing fights with toddlers and eating toast scraps. She lives with her family in sunny San Diego.

Read more stories by Jen Boynton