Composting Overview

Kitchen Composter
Compost container for collecting kitchen scraps

Composting is the process of setting aside organic waste items in a manner that allows nature to decompose the material into a nutrient-rich, water-retentive soil additive that improves soil structure. Commonly composted items include plant-based food scraps from the kitchen, coffee grounds (with the filters), eggshells, napkins, paper towels, shredded paper, raked leaves and lawn clippings.

Why Compost?

Composting converts waste products into a useful nutrient and microbe rich soil amendment that pepper plants absolutely love. Not only does composting help gardeners improve their soil while saving money, it's also incredibly eco-friendly!

  • More DIY composting means a reduced need for harvesting, packaging and transport of commercially sourced soils and fertilizers.
  • Composting helps reduce landfill waste. The average person is said to throw away 270 pounds of compostable food scraps a year. Not to mention, a reduction of discarded store-bought soil and fertilizer packaging.
  • Composting helps reduce greenhouse gases. Compostable materials sent to landfills are likely buried and undergo anaerobic decomposition – producing methane gas, which warms the planet up to 86 times more than CO2. Whereas, properly composted material results in aerobic decomposition having CO2 as a byproduct.

How to Compost

Fresh Compost in Rotating Drum
Ready for use compost in rotating drum – just a few eggshell fragments and twigs remain

There are many, many ways to compost. Entire books have been written on the subject, and the science and methods are continually evolving. Choosing a way, or ways, to compost typically depends on a few commonly considered factors…

  • What's to be composted?
  • How much material is to be processed?
  • Available space?
  • Cost and effort?
  • For personal use or resale?

That said, getting started in composting is easy! With even a small amount of space and a smidge of knowledge, a beginner can quickly assemble a simple composting system. Here, we overview a few common composting methods as a starting point, and then provide more detail on the ways we recycle our organic waste.

Compost Piles and Bins

A compost pile is a simple and inexpensive way to compost. This works great for grass clippings, fallen leaves and wood chips. Simply place them onto a pile and, roughly once a month, turn the pile. Turning the pile consists of using a pitchfork or shovel to invert the pile or to thoroughly mix it up. Doing this aerates the pile – allowing for an aerobic decomposition.

When a pile starts to get large, simply start another pile and continue to turn the other pile(s) until sufficiently decomposed. Adding kitchen scraps to compost piles can attract unwanted animals that feed on the scraps. Some find that burying the scraps within the pile is enough of an obstacle to keep animals away.

A compost bin takes this a step further by using pallets, spare wood, or wire fencing to build an enclosure(s) for the compostable material. This is helpful for processing more material in a smaller space and makes the area look more tidy. Adding a lid and keeping enclosure gaps small can be done to keep out animals – if kitchen scraps are to be added. If insects become an issue, lightly burying fresh scraps can help.

Rotating Drums
Rotating Drum Outdoor Composter
Rotating drum outdoor composter

A rotating drum is useful for composting kitchen scraps without attracting animals. It's also a tidy way to compost in a suburban backyard, and the rotating mechanism makes it relatively easy to regularly aerate the compost. It can also process a reasonable amount of paper scraps as well as a small amount of grass clippings and leaves.

If this method is used, it's best to have two drums. This allows one drum to be the "fill" drum that's being filled with new material, while the other is the "decompose" drum that's left to fully decompose the previously added material. When the "decompose" drum has fully processed its organic material, it can be emptied and become the new "fill" drum – making the other one the new "decompose" drum. Both drums should be rotated once a week to aerate.

Worm Beds or Vermicompost

Worm beds are a great way to process a small to medium amount of food and paper scraps indoors. A DIY worm bed is easily made out of a plastic storage bin with a snug fitting lid. Holes need to be drilled into the lid to provide fresh air. Only a few red wiggler worms from outside or a bait shop need to be added, as they will multiply quickly. Simply add your food and paper scraps.

The nutrient-rich compost can be periodically removed from the lower portion of the container, while leaving the partially processed material within the bin. When harvesting compost, be sure to leave a few worms in the container to continue processing newly added material.

Hugelkultur Mound
Our Hugelkultur mound; first year

Hugelkultur turns the garden bed into the composter, and is a great way to process new and old logs, branches, grass clippings and leaves. Place a combination of old and new logs on the bottom, directly on the ground (can be placed on bare soil, grass or weeds). Then, add larger branches followed by smaller ones. The mound should then to topped with a thick layer of leaves and grass clippings. It's best to start this process in late summer though late fall so the material has a chance to start breaking down by the following spring.

Before spring planting, a thick layer of soil and/or compost should be added to top off the mound. Adding a layer of straw, or wood chip mulch, to cover the soil is also helpful for retaining moisture, preventing erosion and eventually adding more nutrients as it decomposes. In autumn, plants can be chopped and left on top of the soil, followed by a new layer of compost, leaves and grass clippings. In spring, more soil/compost and mulch can again be added.

Green Matter vs. Brown Matter

There are two types of compostable matter – green matter and brown matter. Green matter is kitchen scraps and fresh lawn clippings (live stuff). Shredded paper, paper towels, napkins and raked leaves constitute brown matter (dead stuff). When doing compost piles or rotating drums, it’s good to use a mixture of both green and brown matter.

Some sources suggest a ratio of 2 parts brown matter 1 part green matter. Others suggest 3-to-1 brown matter to green matter. The goal with these ratios is to produce a carbon to nitrogen ratio of 30-to-1, which is ideal for composting. Though the 2-to-1, 3-to-1 guidelines depend on the actual brown matter versus green matter used. Bottom line… The 30-to-1 carbon to nitrogen goal produces optimal composting, meaning decomposition happens quickest at this ratio. Though, regardless of the actual ratio, decomposition will still occur and eventually you'll get a great soil additive.

What We Do

One of our main gardening goals is to avoid store-bought fertilizers where possible, while reducing and being more efficient with any soil we purchase. The variety of ways we compost and reuse organic matter has helped in growing healthy pepper plants with less trips to the store. Below are the composting and soil management methods that have worked well for us.

Rotating Compost Drums
Our Rotating Drum Outdoor Composters
Our rotating drum outdoor composters; one is in "fill" mode, while the other is left to decompose

An attractive kitchen compost bin can be purchased for around $20-$40 and placed near the cutting board and sink for easy access. In addition to looking tidy, they have a secure-fitting lid with filtered ventilation holes. A secure lid is recommended to keep fruit flies from establishing themselves. Alternatively, any bucket with good lid will do.

To keep things simple (and safer, see Does Compost Have to Reach a Certain Temperature?), we mainly add fruit and veggie remains, coffee grounds and eggshells to our kitchen composter – no meat or dairy products. When full, the contents of the kitchen bin are emptied into the "fill" drum. Periodically, grass clippings are added as well. To introduce brown matter, we also periodically add shredded paper or dead leaves. Similarly, dirtied napkins and paper towels (that weren't exposed to chemical cleaners or other potential toxins) are routinely added to the kitchen collector.

Once the "decompose" drum has finished processing its organic material, it's emptied. Then, the "decompose" drum becomes the "fill" drum, and no new material is added to the prior "fill" drum, leaving it to decompose. For us, this usually produces about 3-4 full drums of nutrient-rich compost a year.

We tend to keep compost in the drum a little past the point where it looks like good soil. The food scraps and lawn clippings contain many seeds. As the compost starts looking good, seeds will start to sprout in the drums. The weekly drum rotation tends to bury the seedlings, killing the plants and lessening the amount of volunteer plants produced when the compost is used. That said, this composting method does tend to leave plenty of viable seeds. When used, we typically add a top layer of soil over the compost to reduce non-intended sprouts.

Compost Piles/Bins

Usually, only a bag or two of lawn clippings can be added to our rotating drums each time the lawn is cut. The rest we either pile, or place in a wire bin. Rather than regularly turning these piles/bins as recommended, we simply add to them over the course of a growing season. The piles/bins, for us, are not usually too large and have enough air access to decompose a decent amount. In early winter, we use these to top off our garden beds, Hugelkultur mounds and pots – followed by a layer of compost, potash and fresh soil. The partially decomposed clippings continue to decompose, providing a slow release of nutrients for next year's plants.


While not a composting method, this is a natural way to capture potassium and other plant micro-nutrients. The key is to collect the ash before it rains (and, after it has cooled), as potassium and other nutrients are likely to be washed away. We add this potash (pot ash) to our rotating drums, raised beds, Hugelkultur mounds and pots.

Hugelkultur Barrels
Our Hugelkultur 55-gallon barrels; better drainage and direct soil contact were added for their 2nd year

We tried a Hugelkultur mound for the first time this year, and had amazing results. Our Hugelkultur pepper plants grew noticeably larger and were healthier. We also experimented with Hugelkultur pots – using 55 gallon food-grade plastic barrels – with mixed results. While the plants did grow and do OK, they weren't nearly as healthy as the peppers in Hugelkultur mound.

These pots were filled with organic matter similar to Hugelkultur mound. In an attempt to conserve water and require less frequent watering, we drilled only a single 1/4" drainage hole about 6-10" from the bottom to store excess rainwater. However, we think this caused an anaerobic condition – reducing beneficial microbes and nutrients. We believe better drainage was needed, and that having direct soil contact would allow for better access to beneficial worms, microbes and fungi. We've recently drilled four 1-3/4" holes into each of the container bottoms for the upcoming year.

Repurposing Potting Soil

We like to grow many of our peppers in pots, for a variety of reasons. After a growing season, we cut the pepper plants into small segments and leave them on top of the existing soil. We then add fresh compost, grass clippings and top with an inch or two of fresh soil. In doing this, we've been able to get 2-3 years out of each pot. After that, we'll empty the pot's soil into a garden or landscaping bed, or use it to top off a Hugelkultur mound.

Buying Quality Soil in Bulk

It's not only cheaper, it's higher quality soil. It also eliminates trips to the store and having to discard the many wasteful plastic soil bags.

Does Compost Have to Reach a Certain Temperature?

It depends… Here again, this is an extensive topic. Depending on implementation and usage specifics, additional research may be warranted.

The decomposition of organic matter produces heat. Too much of certain types of organic matter in a confined space can present a fire hazard. When meats, fish remains, and fresh manure are involved, there's an increased risk of pathogens, and maintaining a high enough temperature over a long enough time period is advised to sterilize. Also, having compost reach certain temperatures for a sufficient duration is needed to destroy weed seeds.

If compost is to be sold or marketed as organic, certain regulations and approved practices apply. In many commercial cases, detailed compost logs need to be kept.

Since we compost for private use and no meat or manure is added, we don't pay attention to composting temperature. We simply wait until the organic matter in our rotating drum has fully decomposed. Our compost is usually buried beneath freshly added soil, keeping most weed seeds deep enough to not sprout. We also wash any garden food before consuming.

Additional Resources