What is a Composting Unit?


Composting units are bins or barrels intended for use in producing compost, a nutrient-rich soil that can be added to gardens. Common home and garden waste is used to make compost, and composting has become a popular way to save money and reduce the amount of trash sent to the landfill or incinerator, all while promoting healthy and fruitful gardens.

Composting Basics

Composting occurs when microorganisms break down organic matter into nutrient-rich soil. Compost requires two components: carbon-rich "brown" ingredients, such as dead leaves or paper scraps; and nitrogen-rich "green" ingredients, such as grass clippings or kitchen waste. Carbon provides the microorganisms with food, while nitrogen promotes reproduction. At the end of the process, you will have humus-rich soil to use in your garden.

Types of Composting Units

The University of Florida Extension classifies home composting units as two types. Holding bin units are containers for holding compost. Turning the compost must be accomplished manually using a garden fork. Holding bins may be constructed of many different materials, from wire fencing to wood or plastic. Turning units are barrel-shaped and, like the name suggests, can be rotated by hand, making it easier to mix the compost. Turning units generally produce compost faster, although volume may be a problem. Both types of units can be purchased from a garden supply store or made at home.


The University of Florida Extension lists several considerations when selecting a composting unit. First, consider the volume of compost that you expect to generate. Holding bin units are easier to move and expand to accommodate larger volumes of compost. Turning units, while they create compost faster, tend to be smaller and are less able to accommodate large volumes. Also consider the time and labor you want to put into composting. Holding bin units require turning the compost manually with a fork to aerate it and speed up the composting process. Turning units, on the other hand, can be rotated by hand using a crank or similar implement, making them less labor-intensive. Finally, consider possible rodent problems. Food scraps in your composting unit may draw animals like rats or raccoons, making units that close and seal tightly essential. In other areas, an open unit may create no problems.

Building a Composting Unit

There are many different ways to build a home composting unit. "Rodale's Ultimate Encyclopedia of Organic Gardening" recommends constructing four wood-and-wire frames and attaching three of them to form three sides of a square. Attach the fourth to the front using a latch and hinge. When you want to turn your compost or need to move the frame to start a new pile, simply unlatch the front and move the structure aside. Return it to place after turning or use it to start a new pile. Old trash cans, barrels and wood pallets are also easily converted into composting units. Contact your local agricultural extension office to obtain plans for building a composting unit.

Composting Tips

As "Grit" magazine puts it, "the world of composting is seldom black and white--or shall we say brown and green?" Intimidating quantities of information about composting exist, proposing specific ratios based on material and myriad methods for producing more and better compost. However, it's important to keep in mind that composting is a natural process. In nature, composting breaks down organic matter, keeping dead plants from piling up and simultaneously nourishing the next generation of growth. You don't need to worry excessively about your brown-to-green ratio and you don't need to turn your compost religiously. Nature rarely replicates these precise conditions either. Bad odors indicate that you need more brown ingredients, while dryness indicates that you need more green. After that, pile scraps into your new unit, and nature will do the work for you.

Keywords: composting units, composting bins, composting barrels

About this Author

First published in 2000, Dawn Walls-Thumma has served as an editor for Bartleby and Antithesis Common literary magazines. Her work has been published academically and in creative journals. Walls-Thumma writes about education, gardening, and sustainable living. She holds a Bachelor of Arts in psychology and writing from University of Maryland, and is a graduate student in education at American Public University.