Composting is the process of transforming food scraps, leaves, and other organic matter into nutrient-rich soil through the work of microbes, fungi, insects, oxygen, moisture, and time.
Our food waste can become a climate solution. By keeping organic materials out of landfills, compost reduces methane emissions while returning nutrients back to the soil to support plants and biodiversity. Healthy soils built with compost are also better able to hold water during droughts and withstand the impacts of extreme weather.
According to Project Drawdown, reducing food waste as number one on their handful of lists as an impactful way to mitigiate climate change. Today the term food waste has gotten a bad wrap online, mainly because the U.S. wastes around 1/3 of all available food going uneaten or loss through waste.
While many American struggle today to afford groceries—corporations for some time now rather waste the food than give it away. And for the longest time the way we have dealt with waste is to send it far away, whether it’s plastic, materials, or food and not think about it.
There is no such thing as waste when you understand that most food is compostable. I became curious about how to build a local composting system after my frustration of not having access to industrial composting. And here’s what I found…
For the third episode of my digital web series, Teaching Climate Together, Season 2, I wanted to learn about composting and what it looks like in practice. Full Episode HERE.
I don’t compost because I don’t have green bins (in my apartment) but that isn’t an excecuse not to find an alternative. I decided to look at what a decentralized local composting system can look like in Los Angeles. Majority of people in America are familiar with the green bin in their city that allows for food scraps, food-soil paper, and yard waste. And industrial composting is helpful in many cases, by processing millions of tons of organic waste.
And while industrial composting in the United States is not perfect, I am thankful for a large-scale system that provides benefits to people. But there are major policy changes that can help states improve the process of composting and also working closer with communities.
I learned about the work of LA Compost, which operates as a decentralized network of community compost hub models. LA Compost has built places at local gardens, churches, schools, and even workspaces to provide accessible places for drop-off composting. They’ve diverted 934,504.16 lbs of organics, preventing over 159 metric tons of CO2 from entering the atmosphere. You can read more about their impact report HERE.
My journey began in Los Angeles—I headed over to Elsyvian Valley Community Garden, an oasis in the heart of Frogtown. With a week's worth of compost in hand, I met up with the Compost Hubs Manager (Maggie Smart-McCabe) at LA Compost to learn about how composting works.
To my surprise, she informed me that the community garden was once a parking lot (back in 2011) and was later repaved into a community garden for residents. Since then, the garden has been growing a variety of fruits and vegetables for the community.
I learned about the term community composting and how the garden provides a place for people not only to learn but also to interact with others. I wanted to understand a little bit more of how the garden is designed, most specifically how their composting system works at this specific location.
How does this community garden handle composting?
What people do when they come to the garden is open one of the chambers and add their food scraps. And then they cover it with mulch or browns. The inside of the box looked spectacular. There were tons of critters and decomposers breaking everything down.
A key component of this chamber is that they layer their ingredients of browns and greens. This process adds carbon to the pile. Adding food scraps adds nitrogen. This recipe is a delicacy for their decomposers. The microorganisms begin to digest the material as people blend the material with air and water. This process generates heat and energy through their metabolism, thereby increasing the box’s temperature and supporting hot composting.
Eventually, the process is repeated until the chamber is full. This process allows them to handle about 1,000 pounds of organic material per month. That’s a lot of compost!
What types of materials can be composted?
There is often a debate about what can or cannot be composted. And I wanted to get clarity. Maggie told me I could compost anything that was once alive. But in community composting, they can accept anything except meat, dairy (yay for vegans lol), or oils.
One of those reasons is pests affecting the garden. She did share that if people have green bins at home, they can accept more items, but that depends on the citys municipality.
But for their local community composting system, they are focused on ingredients that work best for their output. What’s cool about fertilizers compared to synthetic fertilizers is that local composting systems build nutrients and biology into the organic matter, which helps the soil build over time.
It takes a month to fill the first chamber, and once that’s full, a key part of composting is turning it to add oxygen. That is then sent to the next chamber, which is the cooking chamber (we love cooking). The temperature in this range is from 131 to 155 degrees Fahrenheit. Some may say it’s comparable to baking a cake. The cooking stage is important because it helps prevent any spread of pests or pathogens.
For example, if you compost something with powdery mildew on it, you don’t need to worry about it because the heat during the cooking stage prevents any pathogens from spread and even seeds from sprouting.
The stages of composting
Maggie led me to the other side of the garden, where I began exploring the 3 stages of compost, an extension of their 3-bin system. Each compost pile had a different set of temperatures and stages. One pile even contained actinobacteria, indicating that the compost was in its thermophilic stage.
One of the key elements to community composting is the people. The ability of a community to come together and take turns caring for the compost enables a distribution process. And this is important because in today's waste systems, the individual is heavily disconnected from the composting process.
For many people who may not have had any experience with or seen the magic behind composting, it can encourage residents to understand that change can happen within a matter of weeks. Imagine having free organic fertilizer rather than relying on large-scale industrial synthetic fertilizers, which are less environmentally friendly.
My Time At A Soil Lab
After getting my hands dirty at the community garden. I collected soil samples from outside and inside the garden to compare what healthy soil looks like. I headed over to the LA Compost Community Soil Testing Lab to inspect the soil’s health with Alyssa Carillo, the educational program manager.
We compared the two sample jars I collected. She told me there are several methods for measuring soil health. She noted that compost is not soil, but the reason why people use compost is that it provides several health benefits that soil needs to be productive.
At LA Compost, they love to provide tests and accessible guides for community members wanting to get an introduction into soil science. They even have their own magic school bus for kids education. We used an i4 Microscope to see the microbes in real time.
There is so much life in the soil. For example, in a single teaspoon of healthy soil, there are billions of microorganisms. Based on my initial visual observation of the two soil samples, I shared that the soil in the street outside the garden would have much fewer microorganisms than the one inside the community garden, given that compost is a surplus and being added actively to the garden.
With the power of the microscope, we identified broken plant material, and lots of circular dots and rods that were moving, which are bacteria! The larger organisms we noted were protozoa (testate amoeba), and some fungal spores. The other sample I tested (the one that had less productivity), and I found some minerals, but very little activity.
Now, it doesn’t mean that soil is essentially extinct or dead, but that with the power of composting, it can help build a healthy system by adding microorganisms into the soil.
Composting Facility
After learning a bit at the soil health lab on how compost enriches soil health for minerals and lifeforms I got my hands dirty once again at another site just outside the lab.
From food scraps to nutrient-dense soil, familiar sites like the worms and browns all play a part in a healthy decomposition process. Across town, at the Griffith Park Community Hub, an endless pile of compost speckled the large processing center. There, I met with the Founder of LA Compost, Michael Martinez, whose mission is to enhance community empowerment.
Michael shared how he created the organization twelve years ago with the understanding that there’s no such thing as waste on planet Earth. He wanted to explore the stories of food and community. LA Compost began as a group of friends trying to collect food scraps, turn them into soil food, build gardens, and complete the story of food.
Michael wanted LA Compost to focus less on the transactional nature of the waste industry, of placing an item in a bin, and it disappears and goes away, and I no longer have to think about it. He wanted to show the full story of where that goes. Who does it impact? Which communities have to live next to these large-scale infrastructure projects that are causing harm?
LA Compost wanted to showcase local solutions and options that help communities access healthy food, build healthy soil, and support local food systems. For many people, when we think of composting, it can seem far-fetched because low-income residents in Los Angeles have the least access to resources. So I asked Michael how they fill in the gap for people who don’t have any access to composting?
“They might not have access to it, but they have access to infrastructure that receives it. They might not have access to recycling or composting, but they have to live next to incinerators, landfills, or other places that take the brunt of our waste system… We change that narrative—it’s not waste; it’s a resource that shouldn’t have to travel far.
But it’s a resource that stays in our communities not just to support soil but to support the community. With opportunities to be outside, to meet your neighbors, and cultivate community, and to see other ways that they can be resourceful”.
As Latinos, both of us shared how in our culture, nothing went to waste, from reuse, repair, and reduce. He told me that growing LA Compost required strategic partnerships. While many people romanticize creating local collectives, they often fall short due to a lack of structure, funding, and mentorship. And it’s true, I believe that many of us have great ideas, but when it comes to creating a flourishing project, it requires collaboration and strategic relationships.
LA Compost is an example of what can be created with the intent of community, collaboration, and decentralization. He shared that results speak louder than proposals or presentations. In the beginning, they knew they had to do the work well before advocating for scaling. In California, he says state policy matters and using people-first language creates an opportunity for everyone to feel meaningfully involved.
He would read city websites and sustainability plans, and use their language to present LA Compost's vision. He talked about how he positioned the organization as a piece of that solution. He wanted to take people's first language and know it’s a people-powered movement. And I think that is genius because a lot of us who are trying to reimagine systems need to understand that we must at times work alongside the existing systems that exist around us.
All forms of composting are important; local and industrial composting are essential. There is no one-size-fits-all solution to local resource management. Local composting will never achieve the diversion numbers of industrial composting, which is okay, but there are several benefits to creating local composting. Local job creation, environmental stewardship, and the involvement of people in the solution are valuable. There is liberation and freedom in choice in where you want your resources to stay.
Isaias: If the soil could speak our human language, what would it be saying right now?
Michael: If the soil were able to speak, it would remind us: I am not dirt; I am not dust. I am alive. I am alive because there are things inside me that allow me to thrive. There’s the soil food web, microbial life, structure, water, and air porosity. My life depends on yours, and yours on mine.
Composting is truly one of the most coolest climate solutions I have seen. And through the work of LA Compost, I began dropping off my composting at their local hub sites. I usually use their farmers markets drop off map they have listed HERE.
What is your relationship with composting? Share with me in the comments below!
A great story which reminds us that soil is not just a 'holding medium' (as some industrial agricultural systems suggest) but an essential part of the living Earth, and a part which we can participate in in a positive way (as well as a negative way if we don't engage!). Thank you.