This article originally appeared in the May 2018 issue of Resource Recycling magazine. Subscribe today for access to all print content.
Editor’s note: As recycling program leaders around the country look to spark more backyard composting among residents, they need to provide those residents with resources explaining the benefits, the basic steps to get started, and the different methods that can lead to soil success.
A new book lays out the basics, offering a framework of talking points to bring people of all walks of life into the process. The following is an excerpt from “Composting for a New Generation,” which was published by Cool Spring Press and released at the end of 2017. The author is a manager at the Hamilton County (Ohio) Recycling and Solid Waste District.
Upsides in the garden
Imagine taking materials that many people view as garbage and transforming them into something useful. When you compost, you create something that will amend your soil and improve your garden. You create something that has the ability to bind heavy metals so your plants won’t absorb them.
You create something that reduces your need for fertilizers and pesticides. Best of all, creating this special something requires no electricity, and you can make all the tools you need yourself.
Compost holds a special place in the hearts of serious gardeners as the most important soil amendment around. But aside from the many personal benefits you reap from composting, your decision to compost also benefits the world around you, positively affecting larger environmental issues. You win, your soil wins and the planet wins.
Improving your soil
Whether you live in an area with soil so sandy that it holds no water, urban soil that needs some TLC, or heavy clay soil that only the toughest plant roots – or sharpest spade – can penetrate, compost can help. Backyard composting creates a rich, loamy material with beneficial microorganisms that bring life to your soil.
When we compost in our backyards, we condense the decomposition process happening naturally to create a rich, humus-filled material in a matter of a few months to a year. The end product makes plants stand up and cheer with excitement. They’d hug you if they could (or at least give you a high-five).
Mending your soil’s relationship with water
Soil scientists explain that soil structure breaks down to three basic components: sand, silt and clay. Sandy soils with large spaces between particles tend to drain too quickly. Heavy clay soils, on the other hand, have tiny spaces in between their very small particles and can retain too much water and drown your plants’ roots.
Just as a natural humus layer would, compost helps improve the relationship that both sandy and clay soils have with water. The organisms that break down organic material release a sticky, glue-like substance that helps bind soil particles into a crumbly texture. The irregularly shaped clumps of compost-amended soil create spaces for air and act like a sponge to hold water. Compost aerates heavy clay soils by adding more spaces for air and providing the opportunity for water to drain when the soil becomes saturated.
In other words, compost gives your soil the sponge-like, water-retaining quality preferred by most plants. Adding just 5 percent more compost to your soil could quadruple your soil’s capacity to hold water.
As if that wasn’t enough, using compost as a mulch also improves the soil underneath. The compost layer acts like a barrier, protecting the underlying soil from losing moisture through evaporation. Plants in sunny or hot climates are especially grateful for this service; without a protective layer, their soil dries out soon after watering.
Adding essential nutrients to the soil
Plants need 16 essential chemical elements for growth. The most prominent of these include hydrogen and oxygen (typically pulled from the air and water), carbon, nitrogen, phosphorus and potassium. Of course, calcium, magnesium, sulfur, iron, manganese and many others are also important.
Compost helps your plants obtain these nutrients in two ways.
First, compost contains many of these nutrients because the material you added – leaves, food scraps, coffee grounds, and more – contained these nutrients. As the material breaks down in your compost, many of these nutrients become available for plant consumption.
Second, and arguably more important, compost improves the environment in your soil to encourage more microbial activity. The microorganisms in the soil make the nutrients available to your plants and can start pulling minerals from the surrounding soil to feed your plants. Compost improves the living area of the soil for the microorganisms so they grow, reproduce and prosper.
Compost is not fertilizer. People design fertilizer to feed plants. Compost feeds the soil. This distinction may seem minor to those who do not understand that soil is not a barren lifeless matter but a whole ecosystem teeming with life. The compost we add improves the life in the soil, thereby helping to nourish the plants.
Increasing soil aeration
Amending your soil with compost improves the soil tilth. If you have heavy clay soils, the compost will break apart the tight structure, making the soil more friable for better aeration and drainage. Plant roots will have an easier time growing in the amended soil, and the varied structure of the compost will hold small pockets of air for both the roots and the organisms living in the soil.
The gift that keeps on giving, compost also creates a soil habitat where macroinvertebrates thrive. Those little creatures moving around in the soil will continue to keep the soil aerated into the future.
When raindrops hit bare soil, they have so much energy that they can blow apart particles on the surface of the soil. The wet soil particles then separate by size and density, creating layers as they settle, with the finest soil particles settling on top. This process forms a crust on the soil that prevents water from penetrating to the lower layers of soil (and your plants’ roots). The newly formed crust also becomes prone to cracking where the streams of water form while running off. Soil cracking and crust creation begin the process of soil erosion and degradation. A nice layer of compost on the top of the soil cushions the falling rain drops, absorbing the energy and protecting the soil underneath.
The large amount of organic matter in compost also acts like a bonding agent in the soil structure. The compost will hold the soil in place against rain and wind. When you place compost on a sloped area, it will reduce the soil’s natural inclination to slide down the hill. Engineers, farmers and soil conservationists all recognize this benefit and will use compost on sites susceptible to soil erosion. You can also tap into this compost superpower and apply compost to areas where erosion may pull away your soil.
You may have heard the saying “think global, act local.” Backyard composting embraces this philosophy. Setting aside materials from our trash to create a resource for our own backyard can positively affect the environment on a global scale. Sometimes it is hard to imagine that one person or household can really make a difference to something as large as our planet, but imagine the impact if everyone on your block, your neighborhood, or your city started composting in their backyards. What we do matters.
Feeding your landscape, not the landfill
Depending on where you live and how much trash you throw away, compostable yard trimmings, food waste and paper could make up between one-third and one-half of your garbage. In the United States, about 30 percent of the garbage a household creates could easily be composted in the backyard (about 1,234 pounds per year). This doesn’t include the newspaper and cardboard that we could compost but generally recycle.
By composting the material in your backyard, your compostables do not take up space in the garbage truck. The truck will pick up more houses per trip, reducing the fuel needed to collect the route. Your materials also do not take up space at the landfill, extending the life of that landfill and delaying the need to build more. Composting means you put less waste at the curb, leading to lighter garbage and yard waste trucks, longer life at the landfill, and smiles all around.
Reducing your carbon footprint
Backyard composting reduces your carbon footprint, or the amount of greenhouse gases that living your life generates. When plants decompose, they naturally release the carbon dioxide absorbed during their lives. Plants and food scraps also do this in your compost bin. It’s okay; that’s what they’re supposed to do.
But when buried in the landfill with no air, food and yard waste decompose anaerobically and release methane instead. Methane traps heat in our atmosphere and has an impact 25 times greater than CO2 over a 100-year period. In other words, by encouraging the right kind of decomposition, you reduce the greenhouse-gas impact of your yard trimmings and food scraps and lessen global climate change. Yay for you!
Restoring life to our soil through compost also allows soil to amazingly store carbon so that it never becomes CO2 in our atmosphere. This magic trick starts with plants growing in your fertile soil. Plants pull CO2 out of the air in the process we all know and love called photosynthesis. What the plant doesn’t use during photosynthesis is pulled down to the roots and given to the organisms in the soil surrounding the roots. Those soil organisms, especially the fungi, use and stabilize the carbon in a form that the soil can store for thousands of years. A trick like that deserves a standing ovation.
Cleaning polluted soil
We know compost has amazing superpowers, but this one is truly impressive: compost binds heavy metals, polycyclic aromatic hydrocarbons (PAHs) and other nasty toxins in the soil to prevent them from migrating into the water or being absorbed by plants. If you have urban soil with a sketchy past, compost could help improve your soil. Compost microbes are even able to degrade some toxic organic compounds such as petroleum (hydrocarbons). On a larger scale than your backyard, companies use compost to bioremediate soils contaminated with petroleum.
Preventing pollutants in storm water
When it rains, water washes over all the exposed surfaces – driveways, parking lots, farm fields – and picks up and washes away chemicals or materials on those surfaces.
So if you recently salted your driveway or if the farmer recently fertilized his field, rain will pick that up and carry it away. We call this storm water runoff (or nonpoint source pollution). This water and all its hitchhikers end up in streams, rivers, and eventually the ocean. As you might imagine, extra salt, fertilizers and chemical pollutants can cause issues in these aquatic habitats, hurting fish, coral and all the other creatures that call these wet wonderlands their home.
Because compost can bind heavy metals and other contaminants, it acts as a filter for storm water and has been shown to minimize leaching of pesticides and other chemicals in soil systems. We may not have power over what a farmer sprays on his field or what a neighbor’s leaky truck spills on the road, but we can control what happens in our backyard. Any water passing through compost will end up a little cleaner.
You can do it!
After listing more benefits than you probably ever imagined could possibly come from your old banana peel, let me leave you with one last slightly intangible benefit: backyard composting is self-empowering. This benefit goes beyond helping the environment, saving money and improving your garden, which are all benefits with value; each alone could be enough to persuade you to compost. You must experience the empowering feeling to truly understand.
In our consumer-driven society, backyard composting gives us an outlet for creation and regeneration. From the pile of decaying rotten material, once useful and alive, we give death a new purpose. We create a valuable soil amendment with “waste” and our own blood, sweat and tears (though with any luck, not too much blood or tears).
Intentionally, we gather the potato peels, dry crispy leaves and dead plants from last year’s garden. We invite a few billion micro- and macroorganisms and tend to the pile as we would a garden, giving it water, feeding it with food scraps and incorporating air. Backyard composting rewards our attention by providing us the most powerful soil amendment available, ready to transform our tired, spent soil with fresh life and humus.
Over time, compost transforms the landscape from one reliant on artificial fertilizers to an independent, nearly self-sustaining system.
People drawn to backyard composting for the environmental or gardening benefits often continue because of the personal satisfaction that comes from harvesting and using finished compost. I imagine you would get the same feeling from building your own furniture or making your own bread from scratch. It is the satisfactory accomplishment of creating something on your own with no help. After you harvest your compost, you can sit back to admire your creation. You made it, and you should be proud.
Michelle Balz is the assistant solid waste manager at the Hamilton County (Ohio) Recycling and Solid Waste District. She can be contacted at email@example.com and can be found on Twitter and Instagram under @CompostGeek.