Composting is the process by which organic ma-terials, such as yard and kitchen wastes, are decom-posed into a dark-colored, nutrient-rich, soil-building conditioner called humus. In nature, thisprocess occurs slowly when plant and animal mate-rials decompose and their carbon and nutrients arereturned to the ecosystem. By establishing a back-yard compost pile, this biological process can beaccelerated with minimal effort by controllingtemperature, oxygen, and moisture contents. Theresult is a rich, earthy, sweet-smelling humus thatcan be mixed into garden beds, added to flowerpots, or used as a mulch (for perennials andwoody plants). It is an excellent and inexpensiveorganic soil amendment.

Composting reduces dependency on manufacturedchemical fertilizers. Many manufactured fertilizerssupply major nutrients in quick-release solubleforms, while some are slow-release. Long-termbenefits of this method of fertilizing are limited.Plants need more than a few chosen nutrients. In-corporating compost into the soil adds long-termbenefits by improving the soil structure with or-ganic matter. Chemicallytreated soils may lose struc-ture over time and, therefore,require more careful watermanagement to prevent ero-sion, as well as the increaseduse of manufactured fertiliz-ers.

Soil pH is altered by the addition of compost. Theideal pH for growing most fruits, vegetables, andflowers is between 6.0 and 7.5. If your soils pH istoo alkaline (above pH 7.5), compost can helplower it. If your soils pH is too acidic (below pH6.0), compost can help raise it.

Composting recycles wastematerials generated as kitchenscraps and yard products. Bydiverting materials from thewaste stream, the need formore landfills is reduced.

Composting improves soilstructure. Soils in Wyominghave textures that range from

heavy clays to sands. When organic matter is incor-porated, all soils can be improved by enhancingsoil structure and increasing nutrient status. If soilsare clay-like, aeration is important to maintain soilproductivity. It is vital to transform minerals intouseable forms for nutrient uptake by plant roots.Organic matter greatly increases moisture-reten-tion capabilities. By increasing the organic contentof soils, water can be conserved. Organic matteradded to soils through the use of compost acts likea sponge, soaking up and retaining water. Withoutorganic matter, clay soils become hard and watertends to run off or puddle for long periods oftime. On the other hand, sandy soils allow waterto drain quickly. Compost and organic matter al-low greater amounts of water and nutrients to beretained.

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George F. Vance, Soil Science Professor, Department of Renewable Resources

Karen L. Panter, Extension Horticulture Specialist, Department of Plant Sciences

BACKYARD COMPOSTINGSimple, small-scale methods

The amount of time necessary to produce com-post varies, but if you are determined to be suc-cessful, the time it takes to produce nutrient-rich compost is well worth the effort. However,there are several aspects to consider that will re-duce the amount of time and effort required toproduce compost. These include:

Location Keep the compost pile out of thewind and sun so that it wont dry too quickly.

Size The ideal size for a household com-post pile is approximately 1 cubic yard (3 feetwide, 3 feet long, and 3 feet high). If it is toosmall, the pile will not heat up enough to kill weedseeds and other pests or work efficiently. If the pileis too tall, the weight will compact the pile andpush out the air.

Water The pile should be about the consis-tency of a wrung-out sponge. If it is too wet, thentoo little air will be exchanged and the pile maygive off an offensive odor. If it is too dry, micro-

bial activity may slow down enough thatdecomposition is minimal.

Microorganisms Occa-sionally mix in some good gar-

den soil or previously made com-post to introduce microorganisms to your pile.

The microorganisms digest the compost materials,which will heat the compost pile up to approxi-mately 140 degrees Fahrenheit.

Air It is important to provide plenty of air inyour compost pile. This can be achieved severalways: turn the pile frequently (every week or two);use large twigs or poles layered alternately with the

other compostable materials; poke deeply at thepile with a pitchfork or pole; or position yourcompost pile on chicken wire built at least 12inches above the ground, which will allow the airto circulate around all sides.

The best ratio of carbon to nitrogen (C/N ra-tio) for producing compost quickly and with a

minimal amount of effort has been estimatedat between 25 to 30 parts of carbon to 1

part nitrogen. A C/N ratio that is toohigh tends to slow the decompo-sition process, while a low C/N

ratio can lead to nitrogen loss as in-dicated by a strong ammonia smell.

Try experimenting to find what com-bination works best for you. An oldstandby is to alternately layer equalparts of nitrogen, carbon, and soil.

Sources of nitrogen for the compostpile are identified as the green ma-terials: green leaves, lawn clippings,green plant wastes from the garden,kitchen wastes, and barnyard manures.

Sources of carbon for the compostpile include the brown materials:dried matter such as grasses and hays,leaves, sawdust, straw, or almost any other driedorganic matter.

Important factors to consider when determining asite for your compost pile are shade, wind, water,appearance, and proximity to the garden.

Shade The ideal place for a compost pile is inthe shade. If this is not possible, cover the pilewith a layer of straw,hay, or a sheet of blackplastic. This will keepthe sun from dryingyour pile. Keep it awayfrom direct contact withtrees and wooden build-ings as they, too, maybegin to decay.

Wind Keep thecompost pile out of thewind. This will keepyour pile from drying too quickly.

Water Position the pile close to a source ofwater. The closer it is to water, the better you willbe able to maintain the appropriate moisture con-tent.

Appearance Locate the pile in an out-of-the-way site because a compost pile could beviewed as aneyesore byneighbors.

Proximity to garden Consider where thecompost pile will be locatedwith respect to the garden. A wheel-barrow load of compost can be quite heavy.

Quick The secret with this method is for allmaterial to be as small as possible. To achieve this,use a shredder or chop materials finely. Thesmaller the material, the faster the decomposition.Remember that fresh materials are nitrogen-rich.Carbon-rich materials should be added, as well assome soil, to introduce microorganisms. Add wa-ter to make the materials the consistency of awrung-out sponge. Turn or stir every week to twoto mix the composting material and increase aera-tion. This method should produce compost in lessthan a few months.

Medium Materials dont need to be shredded,but they must be layered. Alternately layer carbon,nitrogen, and soil. Turn the pile every four to sixweeks. You should have compost in four to sixmonths.

Slow Alternately layer carbon, nitrogen, andsoil materials, and then just leave it alone. Thismethod takes approximately one year. Checkperiodically for odor. You may need to cover witha carbon containing material or good garden soilto control odor.

Apartment dwellers have even established compostpiles on their bal-conies or in theirkitchens. An easymethod wouldbe to use a 5-gal-lon pail with atight-fitting lid.Use the quickmethod for best results.

Some suggested items that can be used for com-post materials are: garden debris, kitchen wastes(non-meat), shredded paper (beware - some inksmay contain lead), barnyard manure, leaves, hay,straw, grass clippings, sod, toilet paper rolls, saw-dust, wood ashes(ashes and sawdustfrom plywood orparticle board arenot suggested),and dust fromvacuum cleanerbags (dependingon what you havepicked up).

Materials that should not be used in the compostpile are: bones, meat scraps, fats, dog and cat feces,human feces, polyester materials, plastics, synthet-ics, diseased animals or plants, plant debris treatedwith insecticide, toxic material, woody plant parts(may not decompose unless chopped or shred-ded), poisonous plants, and thorny branches.

Pile too wet Add dry ingredients to absorbwater; temporarily increase turning to once everyday or two.

Pile too dry Add more wet ingredientsand/or water so the pile is the consistency of awrung-out sponge; cover with black plastic orstraw.

Pile not working See Variables for Success.

Offensive odor A strong ammonia smell indi-

cates there is too much green material in thepile; add brown materials.

Leaves (or newspaper) matted Try to breakup the mats, adding looser materials and/or soil;next time, shred materials before adding them tothe compost pile.

Flies Turn pile more frequently; covercompletely with soil and straw.

Because of Wyomings cold winters, compostingtime typically takes longer. For example, the coldair may not allow the compostpile to heat up adequately,thereby slowing the process. Bycovering the pile with a sheet ofblack plastic and adding morenitrogen-rich materials, you canmaintain the proper tempera-ture for decomposition (120 to140 degrees Fahrenheit). Making your pile ap-proximately 1 foot taller and wider (any length)will increase its insulation capacity to maintain ahigher internal temperature.

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There are several types of containers available onthe market or to construct at home. These are notnecessary, but can be very useful in maintaining acomposting pile and confining it to an aestheti-cally pleasing area. Materials for the structures arevirtually unlimited. Structures can be made fromwood, wire, plastic, concrete blocks, bales of strawor hay, and more. Research the subject and talkwith fellow composters to determine what style isright for you.

Mix in garden beds The ideal time to do thisis when preparing thebeds for planting. It is notnecessary to dig toodeeply. The top 6 inchesare ideal for nutrient up-take by most plants.

Prepare soil for new lawns Spread a 2 to 3inch layer of compost over the area to be seededor sodded. Then, till it in to a depth of 6 to 8inches. Then, seed or sod the area as planned.

Add to flower pots Asuccessful mixture for con-tainer gardening is com-post and soil. A higherratio than this could pro-vide too rich of a growingmedium. Adding sand maybe necessary for growingcacti and succulents.

Use as a mulch Compost works very well as atop dressing for shrubs, trees, perennials, etc. As amulch, the compost insulates and protects theplant roots from temperature extremes. It alsoprovides nutrients that will be washed into the soilby rain and snow. A third benefit is that the mulchcontrols weeds. If the plant roots are close to thesurface, care must be taken to avoid injuring them.Be careful to leave room between the compost andthe plant. If it touches the plant, the roots will be-gin to form where they contact the compost. Fortrees and shrubs, start approximately 1 foot awayfrom the trunk and extend the application 6 to 12inches beyond the drip line, except in turf areas.Three or 4 inches of mulch is sufficient.

Give it away If you are producing more com-post than you can use, give it to your neighborsand friends. In turn, they may provide you with anendless source of ingredients for your next com-post pile.

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Earthworms are naturally attracted to compost,which provides them with food. Their tunneling isbeneficial to aeration and improving soil structurebecause their castings are rich in plant nutrients.One pound of earthworms ingest 1 pound of gar-bage and produce 1 pound of rich compost on adaily basis! They can significantly reduce the timenecessary to produce finished compost. Care mustbe taken, though, to turn the pile every week ortwo as the intenseheat may kill them.

For indoor kitchenwaste composting , aworm box is recom-mended. It is best to purchase commerciallygrown red worms (Lumbricus rubellus or Eiseniafoetida) for this project. They are sold as fish baitand are commonly called red hybrids or red wig-glers. See the list of suggested readings for in-depth information on composting with earth-worms.

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Appelhof, M. Worms Eat My Garbage. Kalamazoo,MI: Flower Press, 1982.

N. M. Trautmann and M. E. Krasny. Compostingin the Classroom. Kendall/Hunt Publ. Comp.,1997.

S. Campbell. Let it Rot: the Gardeners Guide toComposting. Storey Comm., Inc., 1998.

Biocycles Staff (eds). The Art and Science ofComposting. J. G. Press, Inc. Emmaus, PA, 1991.

Robert Rynk (ed). On-Farm Composting Hand-book. NRAES-54, Cooperative Extension, Ithaca,NY, 1992.

Liz Ball and Jim Anderson. Composting. WorkmanPubl. Comp. Inc., 1997.

L. Nancarrow and J. H. Taylor. The Worm Book:The Complete Guide to Gardening and Compostingwith Worms. Ten Speed Press, 1998.

N. J. Ordra and B. Ellis (eds). Soil andComposting: The Complete Guide to BuildingHealthy, Fertile Soil. Houghton Mifflin Comp.,1998.

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University of Nebraska-Lincoln. NebGuide,(February15, 2001).

The Compost Resource Page(February15,2001).

Ohio State University. Composting at home.,(February15, 2001).

Colorado State University. Composting YardWaste., (February15, 2001).

Also, several magazines have frequent articles oncomposting and compost structures. A few ofthem include:

Biocycle

Family Handyman

Mother Earth News

Organic Gardening

Popular Mechanics

Be aware that due to the dynamic nature of the World Wide Web, Internet sources may be diffi-cult to find. Addresses change and pages can disappear over time. If you find problems with anyof the above listed sites in this publication, please contact George Vance, P.O. Box 3354, LaramieWY, 82071; (307) 766-2297; gfv@uwyo.edu or Karen Panter, P.O. Box 3354, Laramie, WY,82072; (307) 766-5117; kpanter@uwyo.edu.

Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, incooperation with the U.S. Department of Agriculture. Glen Whipple, Director, CooperativeExtension Service, University of Wyoming, Laramie, Wyoming 82071.

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Senior Editor: Tonya Talbert, College of Agriculture, Office of Communications and Technology

Graphic Designer: Tim Schaebethal, Fabricated Designs