New Yorkers have been through a lot over the last couple of months, but this felt personal: The city stopped picking up curbside compost this week and asked residents to instead discard their food scraps and yard waste with their trash.
The Sanitation Department cited budget cuts related to the pandemic, and a spokeswoman said the suspension was “not a change we take lightly.” Many environmentalists, though, said the decision was shortsighted and urged leaders to maintain the composting program. Their bottom line: The city shouldn’t reverse progress on the larger, longer-term crisis of climate change.
“We have too much at stake,” Anna Sacks, an activist who focuses on trash, recycling and compost, said at a town hall meeting on Tuesday.
The program, which involves the participation of an estimated 8 million New Yorkers, “isn’t like a sewage plant that you can turn on and off,” Ms. Sacks said. “If we stop that for 14 months, it’s not going to come back as it is now.”
I’ve been composting at home for seven years now. It helps the climate because it prevents food scraps from going to landfills where they release greenhouse gases. Organic material that ends up in landfills is broken down in an oxygen-starved process known as anaerobic decomposition, which releases methane, a highly potent greenhouse gas. Some of the largest methane emitters in the country are landfills, and, adding insult to injury, the anaerobic decomposition that happens in landfills also smells really bad.
Composting beds instead rely on naturally-occurring aerobic microorganisms that live in the moisture surrounding the organic matter and break down food scraps into heat, water and carbon dioxide. The heat kills harmful bacteria and pathogens, and the carbon dioxide emitted is no more than what’s released in the natural cycle of plant life. Much of that carbon, moreover, is sequestered in the soil, which is rich in nutrients that can be used for community gardening or agriculture.
Environmental groups in New York estimated that the city’s composting programs diverted 118 million pounds of food scraps from landfills last year, capturing more than 42,000 tons’ worth of greenhouse gases in the soil. That’s the equivalent to the emissions from burning almost 50 million pounds of coal.
New York City’s suspension doesn’t mean all composting has stopped. Composting services that previously catered mainly to restaurants and other businesses before the coronavirus outbreak are now starting to service households. Common Ground Compost, for example, makes contactless collections from homes in Manhattan for a fee.
But paid composting services can be expensive. What are some other alternatives?
I use a simple method that’s become popular in my home country, Japan, over the past decade — but, surprisingly, it’s almost completely unknown in the United States. Unlike other home methods like bokashi, it doesn’t require expensive equipment. (Or worms!) Some of the materials we use in Japan might be hard to find here, but they’re easy to substitute.
You just need a large cardboard box, coco peat, which is made from coconut husks, and kuntan, or rice husk ash, which is used widely in Japan to improve soil health. Together, the coco peat and kuntan create the ideal conditions for oxygen-hungry aerobic bacteria to thrive, which then help decompose food scraps.
You can order coco peat online from garden shops. I’ve never seen kuntan for sale in the United States, but you can use horticultural ash like hardwood ash.
Because the cardboard box method involves aerobic decomposition, the compost doesn’t smell. And, the highly-absorbent ash captures moisture, so there isn’t any icky liquid or sludge to deal with. In fact, our compost box sits in the corner of our living room. We do keep a cover on it to prevent flies, and, in seven years, we’ve never had a problem with insects.
“You just have to create an environment that has a lot of oxygen and where natural microorganisms can thrive,” said Kayoko Kondo, a researcher in the Department of Environmental Design at Kyushu University who helped popularize the cardboard box method in Japan. “It really allows you to start seeing food scraps not as something you toss in the trash, but something you can return to nature with your own hands.”
Some quick tips: Use any large cardboard box — not plastic or metal, which won’t let the compost breathe — and reinforce the bottom of the box with an extra layer of cardboard. Raise the cardboard box on some blocks to further improve air flow. Use roughly three parts coco peat, two parts ash. We use a tea towel, secured with string, to cover our box. These instructions are in Japanese, but you might find the illustrations helpful.
We’ve found that a good-sized box can process upwards of 1.5 pounds of fruit and veggie scraps a day, as well as things like eggshells and fish bones. Stir the compost frequently — you’ll find this isn’t a chore, because it smells of earthy goodness.
You can keep using the same box — I’ve had the same one for years now, and compost only accumulates very slowly. If it does start getting full, put some on your houseplants.
My living room compost box still uses kuntan, but I’m planning to start a second one using hardwood ash, so keep an eye on Climate Fwd:, our weekly newsletter about climate change. And, I’m happy to answer composting questions. You can reach me on Twitter: @HirokoTabuchi