Composting has some benefit to the environment, if done right. Here’s how | CNN
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Toss the orange rinds, banana peels and other produce scraps into the compost bin. Mix, repeat.
For some, composting is done without a second thought. For others, it’s a confusing process that may not seem worth the hassle.
Composting is one of many ways people can reduce their negative impact on the planet, but is it worth the effort?
In short, yes, but only if you do it right.
This food recycling process does not have as great an impact as other climate-saving measures such as throwing away less food, but it’s still an important practice, said Dana Gunders, executive director at ReFED, a nonprofit that focuses on how to reduce food waste in the United States.
Food scraps produce harmful greenhouse gases in a landfill and little to none in a compost pile, Gunders said.
Food waste accounted for 24% of trash sent to landfills – that volume is more than any other type of everyday garbage material, according to a 2018 report from the United States Environmental Protection Agency.
There will always be food scraps like banana peels, so you can prevent nutrients from being lost in the landfill by composting and using the soil in your backyard, Gunders said. When you compost, the nutrients return to the soil for further use. When it goes to a landfill, the nutrients are trapped among the trash and doesn’t help anything grow.
“When you add up those scraps around the country, it’s quite a lot of material,” she said.
The art of composting involves mixing the correct ratios of organic matter like food and yard waste with nitrogen, carbon, moisture (like water), and air to accelerate the decomposition of unwanted scraps. That’s according to Sally Brown, research associate professor in the School of Forest Resources at the University of Washington in Seattle.
This environment lets microbes eat the compost contents quickly, turning it into very fertile soil, she said.
It takes anywhere from four to six months for the matter to decompose. A compost pile needs to heat up to about 131 degrees Fahrenheit (55 degrees Celsius) to decompose properly, so in warmer climates like Florida it takes less time to break down than in colder climates like Seattle, according to Brown.
The soil can be used to grow new plants or to nourish plants already growing, which completes the food cycle, she said.
In her garden, she frequently uses homemade composted soil to feed her vegetable plants. “You never question it once you get your hands in that dirt, you see how beautiful it feels, see the worms squiggling around and then see how productive your soil is,” Brown said.
Composting has gotten a bad rap for smelling, but it shouldn’t stink if done correctly, according to Brown. When a compost pile isn’t properly aerated, it’s because it’s anaerobic, meaning oxygen isn’t reaching the pile, she said.
The same phenomenon occurs with something everyone is familiar with – farts. “Your intestinal tract is generally anaerobic, and the gases that come out when you fart are not dissimilar from the gases in a compost pile,” she said.
If a compost pile is anaerobic, there are more serious consequences than the stench.
When a pile doesn’t have oxygen, it emits methane, a harmful greenhouse gas, according to the United States Composting Council.
This is one of the reasons why landfills harm the environment. The waste in landfills is stored under anaerobic conditions because the trash is tightly compacted with little space for oxygen, so the organic material in them creates multiple gases, half of which is methane, according to the United States Environmental Protection Agency.
Methane is an incredibly potent greenhouse that has around 80 times more warming power than carbon dioxide in its first couple of decades in the atmosphere. And it’s responsible for about a third of the climate crisis, according to the United Nations Environment Programme. US landfills released about 109.3 million metrics tons of the carbon dioxide equivalent of methane in 2020, which is around 16.8% of US methane emissions created by humans, according to the EPA.
US landfills released about 109.3 million metrics tons of the carbon dioxide equivalent of methane in 2020, which is around 16.8% of US methane emissions created by humans, according to the EPA.
Luckily, it’s easy to prevent compost from producing methane. When a pile is aerated, meaning it’s exposed to oxygen, methane-producing microbes are not active, so methane is not created, according to the Department of Primary Industries and Regional Development in the Government of Western Australia.
Composters should turn a pile every two to five weeks to keep it aerated, according to the University of Illinois Urbana-Champaign.
Brown materials such as dead plants help aerate the mixture, so having a sufficient amount of those in the pile can help too, said Nena Shaw, acting division director of the Resource Conservation and Sustainability Division in the Office of Land and Emergency Management at the EPA.
There are multiple composting methods such as backyard composting, according to the EPA.
Compost bins should be set up in a dry, shady area, the environmental agency said. Then, add in a combination of brown materials such as dead leaves and green material such as grass clippings and moisten them as they are placed in the bin.
Cover the top of the pile to lock in the moisture and turn the pile when needed until the bottom material looks dark, which means it’s ready to use as soil.
“I love gardening, and so I think what got me into it is the ability to have nutrients for the garden,” Gunders said.
Composting also brings awareness to the environment and the natural cycle of food growth and waste, she said.
When learning to compost, invest in a compost tumbler, Gunders recommended. The bin rotates like a washing machine, making it easy to aerate.
The Old Farmer’s Almanac offers a composting guide that includes how to set up a pile and what can and can’t be composted.
If the do-it-yourself method seems too difficult, many cities offer composting services that pick up people’s organic scraps then compost it at a commercial facility.
If you’re concerned about the footprint of such services, vehicles emit multiple gases, but the majority is carbon dioxide, according to the Green Vehicle Guide. And because methane is so much more potent than carbon dioxide, the amount of carbon dioxide emitted from a vehicle picking up compost material is nowhere near the amount of methane the same material would produce in a landfill, Brown said.
“You could basically drive the compost from California to Oklahoma and still come out ahead,” she said.
Commercial composting can also handle more types of waste that a backyard compost couldn’t, Shaw said.
The higher temperatures of commercial composting allow meat, bones and dairy products to be composted, which wouldn’t work well in an at-home compost, she said.
However, backyard composting is great at recycling produce scraps and yard waste that turn into a usable soil for home gardens, Shaw added.
Commercial nitrogen fertilizers take a lot of energy to manufacture and are expensive, said Joseph Heckman, extension specialist in soil fertility in the department of plant biology at Rutgers University in New Brunswick, New Jersey.
Soil produced from composting helps alleviate the need to use commercial fertilizers, builds soil health, and make crops and soils more resilient in a drought, he said.
The nutrient-rich soil can be used in gardens, yards or anywhere people have plants. For those who do not need the soil, they can give it to farmers who produce crops, Heckman said. The compost needs to meet certain regulations for it to be used on a farm, he added.
In addition to creating rich soil, composting also lessens how much waste a person produces, said Tara Scully, associate professor of biology and director of the sustainability minor in the department of biological sciences at George Washington University in Washington, DC.
She grew up composting with her family and has been doing it herself for the past 20 years after she moved into a house with enough space to do it. Since composting in her own home, Scully noticed much of her landfill waste has been diverted to her homemade compost pile.
“It has significantly reduced our trash each week, I hadn’t realized how much scraps we threw away,” Scully said.