Composting
How to Choose or Make a Bin
Introduction
Composting is a great way to reuse yard waste and reduce household waste, while creating a natural fertilizer for your garden. To compost materials, you need a small outdoor unit in which waste materials can break down. Compost units can be bought or made relatively cheaply and easily.
Choosing a Unit
Regardless of whether the compost unit is purchased or built, you should consider the following items when you choose a unit.
Appearance
The appearance of the unit may be very important in some areas, either because of personal taste or deed restrictions and other limitations. (As a matter of fact, in some areas it is either illegal or a violation of deed restrictions to have a home compost unit.) Units that have been constructed from wood or masonry can be painted or stained to match the decor of your house or to blend into the landscape.
Size of Unit
For people with large quantities of material to compost, many home compost units--such as small barrel units with a capacity of thirty or sixty gallons--are too small. Large barrel units are also difficult to turn when the yard waste has been reduced in volume and is very wet.
Another limitation of many barrel units is that their volume is not large enough to effectively retain the heat produced in the composting process. The barrels do not achieve the necessary temperatures for weed seed destruction when not enough heat is retained. However, they will still produce a composted material over a longer period of time, and some of the larger barrel units can achieve the higher operating temperatures.
Cost
Manufactured compost units--such as wire bins--can be purchased for approximately $40. However, some of the large turning barrel units may cost more than $300. Most manufactured compost units are available for approximately $100.
Compost units can generally be constructed by the homeowner for considerably less cost. Some compost units are relatively easy to build, while others require carpentry or masonry skills to construct.
Wildlife
Rodents and other wild or domestic animals may be a problem in some areas. In those cases, the compost unit should be enclosed and secure, with a sturdy cover.
Wait Time
In general, the compost units that will provide compost in the least amount of time are also those which require the most management. They will require more frequent turning and more attention to placing the proper proportions of materials in the compost unit.
Making Your Own Unit
There are at least as many different ways to construct a compost unit as there are people who build them. If you decide to build a compost unit, the first step is to decide which type of unit is best for you.
Many of your county Extension offices have composting demonstration projects with homemade compost units. Most of the manufactured compost units which you see in manufacturers' literature or in magazines will suggest ways in which to build your own unit. Many magazines, organizations, or Extension offices in other states also have information available.
Types of Units
Compost units can be classified as "holding units" or "turning units." Holding units include bins that have been constructed from masonry, plastic, wood, wire, or a combination of these materials. Most manufactured bin units are plastic or wire. Turning units include barrels that are turned horizontally or end to end.
The bin composting units should be at least three feet wide, three feet long, and three feet high. Larger volumes will work better because of increased heat retention. Two- or three-bin units can make it easier to turn the composting material, particularly if one bin is not large enough to handle the yard waste.
Holding Bins
The holding bin unit is the most popular type of home yard compost unit. The simplest and least expensive type of bin compost unit can be constructed from wire fence material. If you can obtain it, snow fence works quite well. Consider using vinyl-coated fence wire, which is now available at building supply stores. You may also want to consider splitting the cost of a roll of wire with neighbors or friends.
Wire
The length of wire needed for a circular unit will be approximately three times the diameter of the bin. You can wire together the ends of the fence, or use a steel rod or post to permit quick disassembly for removing the compost or for turning the composting material.
If wood or steel corner posts and/or other side support is provided, wire bins can also be square or rectangular. Unless extensive side support is provided, these units can be unsightly. Additionally, they may dry out very easily due to the large amount of open area on the sides and top of these units, while excessive water can collect in these areas during rainy weather. To prevent these problems, some manufacturers of wire bins now sell plastic liners with some holes for aeration. Add a cover to your bin if wildlife or excessive rainfall is a problem.
Wood
You can also construct bin units from lumber or landscaping timbers. Although these units are more expensive than the wire units, they can also be much more attractive. Units made from landscaping timbers can be constructed similar to a log home, and they can be painted or stained to match your home or landscape.
Some attractive units can also be made by using lattice panels in wood frames. Dimension lumber can be used to construct panels, sometimes with slanted side boards to permit aeration.
A very inexpensive bin unit can be constructed by fastening four wood pallets together at the corners with wire or posts made of wood or metal. A fifth pallet can be used for a lid if needed.
Concrete
Concrete blocks are another alternative for your bin compost units. You can build a nonpermanent unit by stacking the blocks and driving steel posts through the holes and into the soil. The blocks can also be mortared or fastened together with surface-bonding materials. To make sure your bin will be aerated, leave ½ to ¾ inch gaps between the ends of the blocks, or turn some of the blocks on their sides to achieve the same effect. The concrete block units can be very attractive if they are painted to match the house or landscape.
Other Materials
You can also make a simple bin compost unit from large metal or plastic trash cans. The only modification required is the drilling of aeration and drainage holes. Although these units have a limited capacity and do not retain heat well, they are easily mixed by emptying the unit and refilling it.
Turning Bins
Turning units will produce compost more quickly than a holding unit if they are intensively managed. However, many manufactured units do not have a large enough volume to allow them to effectively retain heat or to handle the waste from many yards.
Plastic
Plastic barrels are most commonly used to make turning units. They are available in many places that handle mineral oils, detergents, or similar products. Make sure to avoid using barrels that may have contained hazardous or toxic materials.
Barrel compost units can be turned on either the vertical or horizontal axis. Steel pipe and pipe flanges are convenient ways to mount the barrels on supports made from wood or concrete block. Some barrels have a large screw-on lid for loading and unloading. You can make a door on other barrels by cutting a hole in the side or end and using a piano hinge and a latch. Drill holes in the barrels to provide aeration and drainage of excess water.
Adapted from:
Construction of Home Compost Units (AE23) by Roger A. Nordstedt and Anne W. Barkdoll. Published by: Agricultural and Biological Engineering Department (rev. 6/2003).
