A GREENER YOU
Sustainability expert Kristy Drutman of Brown Girl Green simplifies the complexities of composting.
The basic premise of composting is simple: Biodegradable waste (food scraps, coffee grounds, old leaves) returns to the ground from whence it came. But composting can be more complex than you think. We’re here to demystify the process so you can make it a regular part of your routine.
What exactly is composting, and how does it work?
Composting is the process of decomposing organic materials into rich, nurturing fertilizer. Materials are typically a mix of carbon-rich brown matter (straw, fabric, sawdust, wood chips) and nitrogen-rich green matter (grass clippings, coffee grounds, eggshells). The carbon and nitrogen found in compost is a critical food source for healthy microbes that allow for thriving soil.
There are four common methods: hot pile, cold, vermicomposting and electric cycling.
Hot pile, or aerobic, involves tossing green and brown matter into an open pile exposed to oxygen and water. This pile becomes “hot” (ideally 160°F) as bacterial microbes decompose the matter rapidly. However, overheating can cause mold or destroy healthy microbes, so you’ll need to flip the pile consistently to ensure even distribution of moisture and heat. This takes roughly six to nine months to produce fertilizer.
Cold composting, or passive composting, is a simpler but slower method. Just mix brown and green matter in
your compost and let everything decompose into fertilizer over a year or two. However, while less work, this approach can lead to development of unpleasant smells, bacteria, fungi or parasites.
The third method, vermicomposting, is done in an enclosed bin. Organic matter is added to a bed of scrap paper, straw or hay. Then, worms are added to break it down. The worms eat the scraps and their feces becomes a dark, rich compost material called humus. Vermicomposting is generally more expensive than hot pile, but it can be a more flexible option as it can be done indoors or outdoors. Plus, it’s much faster, taking only two to three months to produce compost.
A newer innovation is the electric cycler. This is an indoor bin that dries, grinds and cools food waste to create a dry fertilizer that isn’t as messy or smelly as wet compost.
According to the Environmental Protection Agency, composting reduces reliance on chemical fertilizers, prevents toxic runoff towards oceans and rivers, decreases erosion and diverts waste away from landfills.
Why compost? Don’t compostable items just biodegrade anyway?
DIY composting is one of the easiest, most tangible ways to reduce your carbon footprint. Many think that if you toss your food into a landfill, it’ll decompose all the same. Not true! Food waste in the landfill ends up buried and is not exposed to much oxygen. This anaerobic process results in the production of methane, a potent greenhouse gas that’s driving global climate change. According to the International Energy Agency, landfills remain the third-largest source of human-related methane emissions in the US, after agriculture and nonrenewable energy. Meanwhile, composting is an aerobic process: The waste receives plenty of oxygen, meaning the methaneproducing microbes found in landfills won’t be present in large quantities. With access to air and water, your compost will produce a much richer humus. The humus helps fight off pathogens and can keep you from depending excessively on chemical fertilizers and pesticides. It’s a win for both your home and the planet.
How can I start composting more?
Many cities offer a composting operation that gathers, sorts and processes waste from individual households. Toss your scraps into a curbside “green bin” that an industrial facility will collect and process.
If your city doesn’t offer this service, try DIY! Store scraps (from fruit, veg, eggshells) in an airtight compost container and store somewhere covered, like under the sink, to keep fruit flies away. Do not dispose of meat, grease or bones here, as these may attract pests that can destroy your compost. Transfer the waste into a backyard hot or cold pile, a vermicomposting bin or an electric cycler for further processing. With a little patience, love and nurturing, you’ll have rich, tasty compost for your garden to enjoy!