A Beginner's Guide to Composting—Plus, How to DIY a Compost Bin

Composting is a secret weapon for gardeners—it gives food scraps and other natural waste a second life while serving as fuel for healthy plants. Plus, creating it is actually quite simple. To make compost, all you need to do is compile organic matter—think food scraps, leaves, grass clippings, and coffee grounds—and let it decompose with the help of water, oxygen, and organisms like worms and fungi. The process breaks down the biodegradable materials to make a soil treatment packed with moisture and nutrients, which you can then administer to your plants.

This system is a free and easy way to turn organic waste into something useful, thus decreasing trash pickups and landfill usage. And getting started doesn't necessarily require any special equipment. By following a few simple guidelines and building or buying a compost bin, you can begin your composting journey.

Benefits of Composting

Composting has myriad benefits beyond being a sustainable way to give your plants nutrients.

Improves Soil Health

The organic matter that compost is made out of acts as food for fungus, bacteria, and invertebrates. As the material is broken down by those decomposers, it releases nutrients that are beneficial to your plants and soil. "Compost helps introduce a thriving ecosystem into your soil that continues to interact with the organic material around it, as well as other soil-based organisms, and plant root systems," says Java Bradley of Java's Compost.

Reduces Soil Erosion

Additionally, the organic matter helps with water retention, meaning it protects against the effects of drought. At the same time, compost acts as a sponge, enabling it to absorb almost five times its weight in water. "This helps lesson the impact of storm water, like soil erosion," says Bradley. What's more, compost can function as a filter by immobilizing and degrading pollutants, which improves water quality in local watersheds.

Helps Prevent Plant Disease

By improving soil quality, compost also yields healthier plants that have more resistance to certain diseases. "This also reduces the need for chemicals in our farms, gardens, landscaping, and lawns," says Bradley.

Reduces Waste

Food scraps and materials that would have otherwise gone into your garbage are now used to make compost, thus cutting your trash volume. "This means fewer plastic bags wasted and fewer trips to the dump," says Bradley. Less trash means your carbon footprint is reduced and less material is sent to landfills.

Ingredients for Composting

Successful composting depends on the right combination of "green" and "brown" material. Browns are carbon-rich and greens are nitrogen-rich materials," says Bradley. "Browns usually consist of dry materials like leaf litter, shredded paper or cardboard, sawdust, or yard debris. Greens usually consist of food scraps, fresh coffee grounds, or fresh cut grass." Generally, you want one unit of brown for every unit of green.

In addition to your greens and browns, compost needs air and water. "The aerobic microorganisms that turn food and garden waste into compost require oxygen to support their life," says Erik Stefferud, soils and compost manager at Longwood Gardens. "They get it from air that flows through the compost pile."

Moisture is also an integral component of compost. While it is naturally found in your food scraps, a bit of supplemental water from a garden hose can help. "If there is too much water, anaerobic conditions will result," says Stefferud. "But too little water will slow the rate of decomposition."

Types of Compost Bins

There are many compost bins to choose from, but some are more common than others. Alternatively, you can DIY your own compost bin in a few easy steps.

Open Bottom Bin

Some compost bins sit directly on the ground and have an opening at the bottom. "This allows for the microbiology already present in the soil to find its way into the compost pile and accelerate the process," says Bradley. These bins are great because they never seem to get full as the microorganisms break down the compost. One downside is that they're not as effective at keeping pests from feeding or nesting in your pile.

Tumblers

Tumblers are closed cylinders that are usually raised off the ground. "Closed systems are easy to manage. You just add your browns and greens and turn your compost," says Bradley. Although tumblers are more expensive than some other systems, they're very good at keeping most animals out—some models are made out of galvanized steel and are lockable.

DIY Compost Bin

There are a few ways to make a DIY compost bin, but the easiest technique is to attach five wooden pallets together to make a cube with the top open. "You can throw in food waste and yard waste, and let the pile decompose until it is ready to apply to the garden," says Dan Kemper, expert trainer at the Rodale Institute.

Another technique is to use chicken fencing. Wrap the fencing into a cylindrical tower shape, then drive a 5-foot or 6-foot stake into the ground and attach the mesh to the stake to ensure it stays standing. Similar to the wooden pallet technique, just leave the top open and put in food and yard waste as it is created.  "Always be careful when driving a post into the ground," says Kemper. "Protect your hands with gloves, your eyes with glasses, and your head with a hard hat."

How to Make Compost

Now that you know what should go in your compost and have your bin, you can begin making the natural fertilizer. First, find a spot for your compost bin. Full sun may require more frequent watering, while full shade slows decomposition. With that said, a location with part shade or part sun is ideal.

1. Collect your green and brown materials and deposit them into your bin.
2. Water as needed—the pile should be moist but not dripping.
3. Monitor the pile for temperature ranges—generally between 90 and 150 degrees Fahrenheit—to ensure the microbes are breaking down the materials appropriately.
4. Periodically stir your compost with a pitch fork or a shovel to ensure even composting and provide oxygen for the microorganisms.

You may need to adjust your ratio of greens and browns as your pile breaks down into compost. "If the temperature begins to fall below thresholds, add more fresh greens and turn the compost to add oxygen back to the pile," says Stefferud. On the other hand, if you start to notice the pile is too wet or smells bad, you should increase your browns.  

Signs Your Compost Is Ready

From start to finish, it usually takes three to five months to make a batch of compost. "Once there are no visible food scraps or green garden waste and your compost pile is no longer heating up after mixing, it’s time for it to cure for at least four weeks," says Stefferud. "After curing, expect your pile to shrink to about one-third of its original size." You should be left with finished compost that looks dark, feels loose, and smalls like fresh soil. Most, if not all, of the organic matter should be decomposed.