Anaerobic Composting

Most compost piles are aerobic - they utilize microbes and bacteria that "breathe" air to decompose waste. However, it is possible to compost anaerobically - using bacteria and microbes that thrive in environments that lack oxygen. Anaerobic composting is ideal if you mulch your grass and leaves but you want to compost food wastes. When food wastes are composted in the typical aerobic pile, the food wastes must be buried in the pile to discourage animals from eating your wastes. However, if you are only composting food wastes, simply putting them in a compost pile might attract animals to your pile. This is one reason for composting these wastes anaerobically.

A simple way to make an anaerobic composter is to use several 5-gallon buckets with tight-fitting lids:

1. Cut the bottoms off the buckets, about 1/2" up from the bottom (a saber saw works well; drill a 1/4" diameter hole about 1/2" up from the bottom. Put the saber saw blade into the hole and cut around the circumference).

2. Find an area where you can sink the buckets into the ground. You may need to remove the sod from this area. Sink the buckets into the dirt by twisting them in like a screw. The bottom edge of the bucket should be sunk about 1" into the soil.

3. Put your food wastes into the bucket and snap on the lid. Continue adding food wastes until the bucket is full. Once the bucket is full, leave the lid on and let "compost happen"; it will take 6 months to a year for the materials to completely decompose.

When one bucket is full, start putting your wastes into the next bucket, following the same procedures. The easiest way to remove the finished compost is to pull the bucket up out of the ground and use a shovel to put the compost where you want it.
Once one bucket is full, do not take off the lid to check on the progress. Each time the lid is removed, there is a possibility that the anaerobic organisms may die; this will delay the decomposition process.

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