Composting is the process of turning organic waste into a nutrient-rich soil conditioner. It reduces landfilling, which produces methane gas, which is 84 times more potent than carbon dioxide as a greenhouse gas.
Home composting with this easy and cost-effective approach allows you to safely dispose of kitchen scraps and grass clippings in your garden, where they will decompose quickly over time. A healthy compost pile has an equal balance between green (nitrogen-rich) and brown (carbon-rich) materials for maximum benefit.
How to compost
Composting food scraps is an easy way to reduce waste, combat climate change, and enhance garden soil. Composting is the natural process of decomposition that transforms organic materials like leaves, grass clippings, and kitchen scraps into a nutrient-rich soil amendment. You don’t even need a backyard to start composting! And no matter whether you live in an apartment complex or a suburban home, composting can easily fit into everyday life!
The first step to creating compost piles is collecting materials. The USDA actively encourages people to create their own compost piles, but most Americans send food scraps and yard trimmings straight to landfills, accounting for 20 to 30% of American garbage annually. By doing this, they can produce free soil amendments while decreasing the amount of chemical fertilizer their plants require.
Begin with a 3-foot-square pile placed in an accessible, sunny location that’s not flooded, such as your yard. Combine green materials such as grass clippings and food scraps with brown materials such as shredded paper, dried leaves, hay, or cardboard. Finally, add moisture from sources such as your hosepipe, rainwater, or snowfall; this helps prevent your pile from turning into an unruly, soggy heap and speeds up the decomposition process.
For optimal operation, your compost pile requires an approximately 25:1 ratio of “green” materials to brown materials. However, don’t overthink this ratio: any organic matter, such as paper towels and napkins, will eventually break down under suitable conditions.
You can compost almost anything to reduce waste, not just meats and dairy products. Avoid cooked or oily or fat-laden items, which could attract unwanted pests or cause unpleasant odors. Also, keep any pet droppings, animal manure, or bones out, as these won’t benefit compost. Also, take note of any chemicals on plant materials, as these could potentially kill off microorganisms that aid composting processes.
Materials
Composting transforms organic waste like banana peels and coffee grounds into a soil additive that supports plant growth. Composting also keeps waste out of landfills, reduces methane pollution (a greenhouse gas 25 times more potent than carbon dioxide), and improves soil health through adding organic matter and nutrients.
Composting is an environmentally friendly and straightforward way of diverting food scraps from landfills. But before beginning the process, you must understand which materials are necessary for composting to work successfully.
Microorganisms need the ideal blend of nitrogenous (green) and carbonaceous (brown) materials to produce nutritious compost, such as kitchen scraps and yard waste, and create nutrient-rich compost piles. Green materials, commonly called “greens,” typically include kitchen waste or yard debris. In contrast, carbonaceous material includes dry leaves, twigs, and wood chips, and to create an active compost heap, the ratio should be 3:1 green to brown materials.
Start by designating a dry location outdoors for your compost bin or pile and building or buying a container large enough to store organic scraps. Add layers of brown material, such as wood chips, twigs, and dry leaves, to the bin to keep things warm and airy inside—this layer helps ensure optimal conditions in which to work your magic!
Next, layer in your “greens.” It is best to gather composting materials over several days so that they can decompose more rapidly in your pile. Additionally, you can cut up or shred more oversized items like newspapers or cardboard to expedite the decomposition process.
After combining all the greens and browns, moisten them with water and allow them to decompose. Over time, microorganisms will do their work and turn your organic material into rich soil amendments that you can use to nourish your garden. Organic fertilizers benefit soil health and can increase crop yields while decreasing the use of chemical fertilizers, pesticides, water, or greenhouse gas production.
Setting up a compost pile
Although NRDC recommends consumers minimize food waste, some scraps will inevitably remain. Instead of throwing these scraps away, consider starting a compost pile. Composting is a natural process that turns organic materials like grass clippings, leaves, coffee grounds, and food scraps into nutrient-rich fertilizer by breaking them down with bacteria, fungi, and single-celled organisms (protozoa). As this happens, microorganisms like bacteria, fungi, and protozoa break down material before decomposing further to produce fiber-rich carbon-containing humus that provides inorganic nutrients such as nitrogen, phosphorus, and potassium.
At first, gather enough organic material for at least one cubic yard pile. If necessary, chop or shred any coarse materials to reduce their size; this will allow the microorganisms involved in decomposition to digest them quickly. After collecting enough organic matter, layer carbon and nitrogen materials in appropriate proportions and combine thoroughly using a pitchfork before gradually adding water until the combined materials resemble a damp sponge (50–60 percent moisture content).
An ideal spot for your compost pile should be located downwind from your house to avoid unpleasant odors and help dry out wet materials more efficiently. Furthermore, raindrops could saturate it too heavily and cause it to rot prematurely.
Choose the hot method of composting. Your pile must be at least three cubic feet and enclosed by a cover to allow heat-loving organisms such as thermophilic bacteria to take over decomposition. A thick material such as earth or hay may work best as a cover; other options include plastic sheets or tarps.
As your compost heap heats up, it will turn black and smelly. If decomposition appears to be slowing, it could be because there is too much carbon for every gram of nitrogen (brown). You can increase the C:N ratio by adding manure or grass clippings, or if your pile seems inactive and dry, simply increase brown materials such as wood chips, sawdust, straw, or cardboard.
Maintaining a compost pile
By adding compost to your soil, microorganisms can thrive and perform essential functions for soil health—including helping retain moisture and nutrients, resist erosion, and reduce runoff of pollutants during floods or droughts. Composting is also an environmentally responsible and cost-efficient way to manage household waste while enriching your garden.
To create compost, you’ll need a combination of nitrogen materials (food scraps and grass clippings) and carbon (dry leaves and twigs). This mixture is known as the “golden rule.” A good ratio would be two parts browns to one part greens.
Carbon-rich materials tend to be easier to source than nitrogen-rich ones. Look at cabinet shops or your neighbors for sawdust and shredded cardboard; inquire whether any have dried leaves to give; search online classified ads for wood chips, hay straw, or vegetable peelings as possible sources.
When you add trim and chopped pieces to your pile, nitrogen-rich materials work best. Remember that compost takes approximately one year to prepare, so make sure it is manageable between additions.
If your pile is too dry, it may emit an offensive odor. To fix this problem, add more carbon materials. Conversely, too much moisture in a pile could render it inhospitable to the microorganisms responsible for breaking down organic material and making compost.
Ensuring the pile gets hot enough and breaks down materials faster will accelerate decomposition and compost production.
Once your pile has finished, it should look dark, loose, and crumbly with an earthy aroma. It should also be full of worms and other decomposers, such as vermin. Before using your finished compost in your garden, however, be sure to screen or sift through it first, as certain items, such as twigs or eggshells, may remain undigested and could harm plants.
You can use screened or sifted compost to improve soil conditions, fill flower beds, or add top dressing to vegetable and herb gardens.
