Chicken droppings, like most other forms of manure, make wonderful garden fertilizer. They're high in nitrogen, potassium and phosphorus, all valuable nutrients for most garden plants (see References 1). However, as anyone who has shoveled it will attest, fresh chicken manure is high in ammonia and can burn plants if it's applied without composting. To use chicken manure safely in your garden, it should be composted with a carbon-rich material such as straw.
Droppings and Bedding
Backyard chicken growers and small-scale farms typically use an inexpensive bedding material such as straw, sawdust or wood chips in their henhouses. This bedding helps absorb the manure's odors and surplus moisture, providing the birds with cleaner footing. Fortuitously, all of these common bedding materials work well as high-carbon ingredients for composting. Straw is the most suitable, because it's less dense and is the quickest to break down.
Building Your Pile
A healthy compost pile depends on its ratio of carbon to nitrogen. Chicken manure is high enough in nitrogen to make the usual rules of thumb inappropriate, so use approximately twice as much bedding by weight as manure (see References 2). In practice, you'll probably find you can use the bedding just as it comes from your henhouse. Moisten the mixture of bedding and manure as you stack it, and use a long-stemmed thermometer to monitor the temperature for a few days until the temperature of the pile begins to rise.
Maintaining Your Pile
As long as your pile is at least 1 cubic yard in size, it should quickly begin to heat. Within days, as the straw and manure begin to decompose, the internal temperature of the pile will rise. To reduce the risk of any parasites or harmful bacteria surviving the composting process, the temperature should remain between 130 and 150 degrees Fahrenheit for three days (see References 2). After three days, turn the pile so the materials from the outside move to the middle, where they will also heat and decompose. Repeat this process at least three times.
Curing Your Pile
Once your compost has been turned repeatedly, the temperature will drop. This is normal and simply means the bacteria have finished the initial stage of their work. However, the pile should be allowed to age or "cure" for up to two months before you apply the compost to your garden. This provides an additional margin of safety against harmful bacteria. Leafy vegetables such as lettuce, and root vegetables such as carrots, are the most likely to harbor harmful bacteria. Wash them thoroughly before eating them (see References 2).
Fred Decker is a trained chef and certified food-safety trainer. Decker wrote for the Saint John, New Brunswick Telegraph-Journal, and has been published in Canada's Hospitality and Foodservice magazine. He's held positions selling computers, insurance and mutual funds, and was educated at Memorial University of Newfoundland and the Northern Alberta Institute of Technology.