Function of a Compost Tumbler
A compost tumbler is a device designed to help speed the production of compost. For those unfamiliar with compost, it is a combination of rotted vegetable matter, such as table scraps, fallen leaves, cut grass and other plant debris, which has decomposed. This decomposed matter is an organic mulch as well as an ideal fertilizer which meets any garden's needs. There are four things which compost needs--nitrogen, carbon, water and air. The nitrogen, carbon and water are provided by the contents of a compost pile, but gardeners normally have to turn their piles over every few days to make sure that it gets plenty of oxygen. This is a tedious and time-consuming process, though if you keep your compost pile in a tumbler, you can introduce more oxygen to the pile and increase the rate of decomposition dramatically.
Building a Compost Tumbler
The typical compost tumbler is made using either 45 gallon plastic drum or 55 gallon steel drum. Either work, though the steel drum has to be sealed with rust-resistant paint. The drum is drilled full of holes down its sides to allow oxygen inside. A pole, typically of aluminum or some other rust resistant material is driven through the middle of the standing drum and out the other side. Two more poles, pressure treated wood or more aluminum, are sunk into the ground directly opposite on another. The distance between the two should be the width of the drum plus an extra foot of clearance. Rungs or cups, such as those into which oars lock in rowboats, are mounted to the top of each pole, roughly 3 feet from the ground. The bar passing through the drum is placed within the locks so that it hangs suspended in the air. The compost tumbler is complete.
Using a Compost Tumbler
There are two primary components which go into making compost, be it with a compost tumbler or otherwise. They are soft green components, such as grass clippings and vegetable scraps from the kitchen. They are brown components, such as twigs, leaves, wood chips and bark. The compost tumbler should be loaded with three parts green components for every part brown component. The lid of the drum is pried off and the inside is filled with the composting material. Roughly a gallon of water should be poured into the drum before the lid is resealed. The drum should be capable of spinning around on the pole through its middle, which should be done until the contents are well mixed. The compost tumbler should be spun around again every two days, and water added only when the contents become dry to the touch. In three weeks the compost tumbler should be emptied of the completed compost to make room for another batch.