Composting provides an easy, affordable alternative to purchasing chemical fertilizers for enriching the soil in your garden and flowerbeds. Rotating barrel composters typically produce finished compost more quickly than other composting methods, often in two months or less, according to the University of Illinois Cooperative Extension. Although most barrel composters rotate on a steel rod that is mounted on an elevated stand, you can make a simpler, less expensive rotating barrel composter from a plastic trash can. To rotate your compost barrel, simply turn the trash can on its side and roll it around your yard.
Take the lid off your trash container and invert the trash can on the ground. Drill 10 to 12 5/8-inch holes in the bottom of the trash can to provide enough drainage areas for excess moisture that may collect in your compost. Hold the trash container in place with your hand and drill 15 to 18 evenly spaced holes in the sides of the rotating barrel composter to increase the amount of air that enters the container.
Place the rotating composter upright on the ground and fill it with an equal mix of carbon-rich organic waste (brown organic scraps, such as dead leaves, straw, sawdust and newspaper) and nitrogen-rich organic waste (green organic scraps, such as vegetable peels, cow manure and fresh grass clippings). Shred and chop up larger pieces of organic waste until they're less than approximately 2 inches in diameter to minimize composting time.
Wet your organic waste with a dripping garden hose until it's about as damp as a wrung-out sponge. If you can squeeze out more than 1 to 2 drops of liquid from the compost, then it's too wet and you'll need to add additional carbon scraps to soak up the excess moisture. Toss in several trowels of plain topsoil to introduce aerobic bacteria to your rotating compost unit.
Secure the lid on your rotating compost barrel with a rubber tie-down or elastic bungee cord. Turn the rotating compost barrel on its side and rotate it across the ground five to six complete rotations every five to seven days to produce finished compost within approximately two months' time.