Garbage Today, Dirt Tomorrow
The United States Environmental Protection Agency reports that together, food scraps and yard trimmings constitute 23 percent of the U.S. municipal solid waste stream, with some estimates as high as 30 percent. Now that’s a lot of garbage. Garbage, that is causing landfills to reach capacity creating the need for more landfills. Garbage, that costs the consumer more every day to have hauled away. Garbage that can be turned into a useful, economical product called compost.
Compost is the soil amendment product that results from proper composting. Composting is the controlled decomposition of organic material such as leaves, twigs, grass clippings, and vegetable food scraps. The compost produced by backyard composting is an excellent soil conditioner. Compost is not considered a fertilizer because it does not contain high amounts of nitrogen, but compost will improve drainage in clay soils and increase water retention in sandy soils. Compost helps soil retain nutrients for a slower, steadier release to plants and grasses. Compost can turn poor quality dirt into rich, fertile soil. It also attracts earthworms that aerate the soil and add additional nutrients.
Contrary to popular belief, composting is not a stinking pile of garbage that attracts every type of disgusting vermin. Composting does not require a great deal of time and work, but rather it is easy to do and can be accomplished without expensive, complicated composting bins. All that is needed is a kitchen, a yard and/or a garden and a general understanding of the composting process.
All organic material contains carbon and nitrogen in differing ratios. Straw, dried leaves and sawdust, known as “browns”, are higher in carbon. “Greens”, which include grass clippings, garden weeds and cow, horse and chicken manure have a greater concentration of nitrogen. The proper amount of moisture and air combined with these greens and browns create a habitat for billions of microbes, organisms, fungi and bacteria, which aid in the decomposition process.
Composting can be passive, simply piling up the materials and allowing them to rot slowly, or aggressive, highly managed to produce compost quickly and in large amounts, or anywhere in between. Passive composting requires very little time and effort on your part, but considerable time for the material to decompose, maybe a year or two. The simplest, easiest way to compost is to dig a hole or a trench in the corner of the garden or lawn. Place the yard, garden and kitchen wastes in the hole or trench and cover with an inch or two layer of soil. For every three or four inches of wastes, add another layer of soil.
An inexpensive, three-sided compost bin can be constructed of concrete blocks, discarded pallets (usually free for the asking from local businesses), chicken wire or most any type of building material. Always avoid treated lumber when building your compost bin. Pressure-treated wood, also known as CCA (usually has a greenish tint) contains arsenic, a highly toxic substance. It also contains toxic levels of copper and chromium. Evidence suggests that these toxins leach into the compost from the CCA lumber. The optimal size of a compost pile/bin is 3 feet by 3 feet by 3 feet. This provides the insulation need to maintain sufficient temperatures for more rapid decomposition. Build the bin over soil that has been loosened. This allows worms, bugs and other organisms to migrate upward and aid in decomposition. Alternate the “greens” and “browns” in four to eight inch layers. The exception is grass trimmings. These should be kept to a minimum of two inches as they tend to compact, become slimy and prevent the needed circulation of air. Add water to the browns as they are layered. Ideally the pile should be as moist as a wrung out sponge. At this moisture level, there is a thin film of water coating every particle in the pile, making it very easy for microbes to live and travel throughout the pile. If the pile is to dry, microbial activity slows down which slows down decomposition. If the pile is to wet it will become heavy and compact, excluding air from the pile, causing odor problems and again slowing decomposition.
The average composter will not usually have enough material to create a compost pile 3 feet deep at start-up. No problem, most single-bin composters build an initial pile and add more materials as they become available. The smaller pile will not attain and maintain the amount of heat needed for fast decomposition but it will decompose at temperatures as low as 50 degrees Fahrenheit, it just takes a little longer. After about a year, maybe a little longer, check the bottom of the pile for finished compost. The compost is ready for use when the contents have an earthy smell and resembles course-textured, rich brown soil. When it is ready, shovel out the bottom of the pile and add it to your garden or areas of the yard that needs a little fresh dirt. Most simple piles, after the first few years, will produce a few cubic feet of finished compost yearly.
Aggressive composting involves active participation. A highly managed compost pile can produce finished compost in as little as three to four weeks. The speed with which finished compost is produced depends on the size of the materials, smaller pieces heat up quicker and get hotter, and how often the pile is turned. The temperature of a managed pile is important as it indicates the activity of the decomposition process. The ideal temperature range is between 104 degrees F and 131 degrees F. If the pile appears to be “cooling down”, the microbial activity has slowed. Adding more nitrogen (green) materials such as kitchen wastes, grass clippings or manure will heat it back up. Serious composters may want to use a compost thermometer; they are inexpensive and quite useful for a managed pile.
Air circulation is very important in a managed pile. Most of the organisms that decompose organic matter need air to survive. Periodically turning the pile or mixing the materials will re-oxygenate the pile. The object is to end up with the material that was on the outside of the pile to be in the middle of the restacked pile. Materials that are easily compacted, such as grass clipping, sawdust and ashes should be mixed with courser materials like straw. This will help maintain the needed air. Tree limbs or small diameter PVC pipes can be placed vertically into different parts of a large pile and shaken occasionally for maximum air circulation.
Most any organic matter can be composted, but there are some materials that should be avoided. Meats, bones, fats and oils are very slow to decompose and will draw unwanted pest. Sawdust is best left out of the pile if there is any chance it is from treated (CCA) lumber. The arsenic, copper and chromium used to treat the lumber will become a part of the finished compost and eventually, whatever is planted in it. Pet wastes can contain pathogens, and although the high temperatures of a well-managed compost pile will kill most diseases, they should never be included in the pile. Pet wastes can be buried at a depth of at least 8 inches, but only in areas where food will not be grown. The consistent heat of the compost kills many plant diseases, but it is hard to tell if it has been completely eradicated. If you suspect a plant is diseased it should not be included in the pile. Pernicious weeds, such as morning glory, ivy and some other plants and grasses can resprout from their roots and/or stems in the compost pile. It is usually best to leave them in a sunny, dry place for a few days to make sure they are completely dead before adding them to the pile.
In cold climates the compost pile will go dormant in the winter without special consideration. This is fine. Continue to add kitchen wastes to the pile throughout the cold months and it will start up again when the weather warms. If you want to keep composting year round be sure to place the compost pile in a sunny area to take full advantage of the sun’s warmth. Place straw bales around the sides for added insulation and cover the top with a tarp.
It seems pretty ironic that so many of us pay someone to haul off our garbage and then turn around and pay someone else for the soil conditioners and fertilizers we need for our lawns and gardens. Maybe we should gather up this morning’s coffee grounds and the eggshells. We can add them to tonight’s potato and carrot peelings and yesterday’s newspaper. Yes, even the newspaper can be composted, along with cardboard boxes, if cut into small pieces, and brown paper grocery bags. We can pull a few weeds from the flower garden and add some dry leaves and we have started building a compost pile. It all adds up to less garbage to have hauled away and, in a few months, some rich, dark soils to help our gardens grow.
If the idea of composting appeals to you, but you think you would like more information on the how to’s and what not’s the internet has a world of information. Following are a few web sites that may be helpful: