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Chemicals for Quicker Composting

Compost is organic matter that has decomposed and is invaluable for adding tilth and nutrients to garden soil. A mixture of carbon-based and nitrogen-rich compost materials, kept moist and turned frequently, will usually break down in six months to two years. If your summer season is short, or you need compost quick, consider additives like blood or bone meal, inoculants, or even dishwashing detergent for a quick compost kick-start.

Dishwashing Detergent

Many households accumulate a substantial quantity of non-recyclable paperboard and cardboard (such as cereal boxes) and other paper products. These are composed primarily of wood pulp, and modern inks are usually soy-based and nontoxic, which means these materials can be used as bulk carbon components in your compost. However, they can be slow to break down. The University of Illinois Extension recommends speeding up the cardboard decomposition process by ripping the materials into small pieces, placing them in a bucket, filling the bucket with water, and adding just a few drops of dishwashing detergent (preferably unscented) to the water. Mash the bucket contents around by hand or with a shovel handle a few times a day for three or four days, then pour the contents in a layer on your compost pile between two layers of nitrogen-rich composting materials like grass clippings, kitchen waste or manure.

Blood Meal and Bone Meal

An ideal compost pile combines carbon-based components, like leaves, woodshavings, or straw, with nitrogen-based components like green weeds and fresh leaf prunings or fresh manure. Carbon composting materials are often easier to obtain in large quantities, while nitrogen materials may be lacking, or only available as small amounts of kitchen scraps. Nitrogen can be added to compost in small quantities to make nitrogen accessible to the carbon matter to break it down faster, but the Pennsylvania State University advises against using commercial high-nitrogen fertilizers for this purpose. The "quick fix" of nitrogen fertilizers often simply washes out of the compost pile, creating an excess of nitrogen in the surrounding environment or washing away to create water pollution. Instead, add bone meal or blood meal. Both these substances add concentrated doses of nitrogen to kick-start composting processes, but in organic forms that break down more slowly over time, helping the compost pile as it decays but presenting little threat to the surrounding natural environment.


According to the University of Illinois Extension, inoculants are rich in bacteria and fungi and added to compost to speed up the breakdown of materials. Commercial compost accelerators often contain both nitrogen and a mixture of bacteria and fungi to get to work quickly on your compost materials. If you do not have access to good-quality garden or forest soil, these inoculants can help your compost pile get off to a fast start. Canadian Gardening magazine, however, says that if you have even a small bit of rich soil to throw into your compost pile, you may not need any commercial additives, as a good-quality soil contains a host of organisms that will speed your compost along.

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