What is Composting?
Here in the sustainability office, we are constantly looking for new projects to add to our repertoire of all things sustainable. One of these is composting.
Composting is really just a man-made term for a process done in nature. Food scraps and other organic materials naturally decompose through various biological processes via worms or millions of microorganisms. All that is left over in nature are recycled to become nutrient rich material that is put back into the ground to enhance soil quality.
Recently, I was able to take a tour at Sonoma Compost to observe the human-version of the process.  Located in Petaluma, the small privately owned company has been diverting Sonoma County’s organic waste from landfills since 1985. Nearly 300 tons of materials are dropped off at the site six days a week to be composted. The organization is able to boast that they have diverted over 1,600,000 tons of organic material to date. These materials include: green-waste, non-animal vegetative food-waste, residential yard scraps, trimmings, grape pomace, lumber and even chicken feathers!
Materials are collected in easily identified green yard waste bins and delivered to the site by local municipal haulers. Landscapers, residential, and commercial users are also able to self-haul materials to the site. These materials are all sorted by kind and then prepared to be composted into mulch. After they are initially processed, materials are put into wind-rows where they undergo natural thermophilic (heat-releasing) composting. Microorganisms naturally feed on material in which they will leave behind nutrient rich mulch that can be bought by agricultural growers both small and big. As the microorganisms feed, they release heat by consuming moisture and oxygen. Thus, the rows are drip-irrigated and periodically turned to keep the air and moisture circulating for microbe health. Â Currently, there are a whopping 20 acres of compost in which wind-rows that are ready for harvest will pass through a final screening test to remove plastics. Just last year, Sonoma compost sold 130,000 harvest yards of some of the finest and certified organic mulch.*
Composting is important because it lessens the impact on landfills. Moreover, composting creates compost (mulch) for natural soil enhancement, recycled lumber, firewood, and biofuel. In this case, what’s taken out of the earth is put back in through natural process. Sonoma County produces affordable, certified organic materials that support local farmers and residential users. Also, because Sonoma Compost’s regional location makes it cheaper for residents to recycle yard and wood debris locally. In turn, this reduces greenhouse gas emissions because the materials are not exported to other counties. Lastly, they are able to capture methane (a greenhouse gas, GHG) that is offset through methane-wells in the ground and are able to turn that GHG into electricity that is used locally.*
Because we do some producing of our own, we are currently researching the options for Kendall-Jackson to start collecting green-waste in order to create and use our own compost. We have many opportunities to compost and will continue to find ways to do our part. So, stay tuned!
–Sabrina, Sustainability Coordinator
*Information graciously provided by Sonoma Compost; photo used by permission from Sonoma Compost