IntroductionBackyard poultry ownership provides a great oppor-tunity for improved self-reliance and small-scaleagricultural sustainability through home egg andmeat production. One issue with backyard poultryownership is managing the waste products of yourbirds, particularly the manure and bedding mixture(termed “litter”) that builds up in the coop. If notmanaged properly, this waste material can createodors and attract flies. Composted poultry waste, onthe other hand, can be an excellent resource foramending and fertilizing garden soils.

For the backyard agriculturist, proper compostingof poultry waste has no downsides. It is a convenientmethod for eliminating problematic waste, providesa good source of nutrients for the garden, improvessoil texture, and creates the opportunity for sustainablehome food production. It is a worthwhile process tolearn and employ.

This publication provides basic information on howto properly process backyard-poultry waste and use itin your garden. In urban settings, the properprocedures for composting poultry litter are critical

for maintaining sanitary conditions and positiveneighborly relations. Before starting a compost pile,check with your local city or county government tofind out if there are any regulations or ordinancesgoverning poultry waste disposal in your area.

Managing safety issuesHarmful bacteria, particularly E. coli and Salmonella,may be present in poultry manure. Not all poultrywaste is contaminated with these bacteria, but allpoultry waste should be treated and handled asthough it might contain these pathogens.

Be sure to take precautions when handling poultrylitter to minimize potential health risks. First, washyour hands and clothing thoroughly after handling thebirds or their waste. Second, if using litter as a sourceof organic matter and fertility in the garden, employ aminimum 120-day waiting period between applicationof the litter and harvest of the produce.

The 120-day curing period is needed to allow time forthe natural death of harmful bacteria. The waitingperiod can occur while the litter is in the compost pile,or it can occur after its application in the garden. The

CIS 1194

University of Idaho • College of Agricultural and Life Sciences

by Lance Ellis, Stephen Love, Amber Moore, and Mario E. de Haro-Martí

Composting and using backyard poultry waste in the home garden

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critical safety factor is the 120-day interval between thetime poultry litter is added to the compost pile orgarden and the time the vegetables are harvestedand consumed.

In practice, poultry manure composted for a minimumof 120 days can be applied to the garden in either fall orspring with fewer health safety concerns. Raw manureshould not be applied to seedlings or growing plantsbecause it is a possible source of contamination to ediblecrops. If applying raw manure to the garden throughsheet composting, it is essential that 120 days areallowed to pass between its application and the harvestof vegetables from the garden. If a garden is planted ona typical seasonal schedule, this safety requirementcannot be met with spring applications of raw poultrywaste. Consequently, for reasons of personal safety,direct applications of non-composted poultry manureshould be made only in the fall.

If applying composted poultry litter to the garden, do soprior to planting time. It is not recommended to applycomposted litter when plants are sprouted and growing.It is best applied in either the fall or early spring.

Composting methods Using conventional methods of composting poultrylitter is not absolutely essential. If proper considerationis given to safety concerns, raw poultry manure can beapplied directly to the garden through sheet compostingwith successful outcomes.

Other methods of composting, especially active pilecomposting, however, provide a number of distinctadvantages, including better control of quality in the

final product, minimization of weed seeds andpathogenic organisms, and reduction of salts and otherfactors potentially detrimental to garden plants. Forthese reasons, conventional composting isrecommended and information on using raw manure inthe garden is limited in this publication. If you chooseto apply raw manure, use the recommendationsprovided for sheet composting.

Two methods are commonly used for compostingpoultry litter, the active pile method and sheetcomposting. Each has advantages and disadvantagesdepending on the individual circumstances of eachpoultry owner. For full descriptions and a guide tocomposting, see the University of Idaho Extensionpublication Composting at Home.

Active pile composting

This traditional, common method of composting isdone by making a large pile of litter, adding andmaintaining sufficient water to make the pile moistthroughout, and turning the pile regularly to addoxygen until it has completely decomposed. Thelength of time to complete composting depends onpile temperature and the attention given to thecomposting process (frequency of turning, moisturelevels in the pile, and the initial makeup of the pile’scomponents). Active pile composting takes effortbut results in a high-quality product that can beadded to the garden with confidence. There areseveral ways to do active pile composting, asdemonstrated in figure 1.

The active pile composting method can work wellfor poultry litter with a proper carbon to nitrogen

Figure 1. Backyard composting systems. From left to right: three bin composter, tumbler composter, enclosed static bin. At farright is the start of a pile.

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ratio. Some adjustments in the process may beneeded if poultry manure makes up more than 50%of the initial litter mixture. In this case, you maynotice the development of strong ammonia fumes.You can remedy this situation by adding more carbonto the mixture. This is done through adding “brown”waste (additional straw, dried leaves, dried grassclippings, pine shavings, or shredded paper, etc.) tothe compost pile.

Deciding when the compost is ready for use is subjectto personal judgment, but there are a few importantsigns of adequate aging. Fully composted poultrylitter will have no offensive odor and no recognizableparticles of straw or bedding (figure 2).

Sheet compostingThe second method for composting poultry manureis commonly referred to as sheet composting. This isdone directly in the garden by applying a layer ofraw (uncomposted) poultry litter to the soil andeither leaving it on the surface to decompose orlightly tilling it in.

Sheet composting is easy, but control over productquality is low. Also, it creates a situation where itis difficult to manage harmful bacteria. Lastly, thelitter may introduce unwanted weed seeds. Litterapplied directly to garden soil does not heat up theway it does in a compost pile. Without the heatingprocess to kill weed seeds and pathogens, the littermay introduce these unwanted contaminants tothe garden.

Proper timing is essential for the sheet compostingmethod to be safe and successful. Apply the poultrywaste during the fall after the garden has been har-vested. This will allow ample time for the rawmanure to decompose and for nutrients to beconverted into a more usable form for optimaluptake by garden plants the following spring. It

also allows undesirable salts to leach away. Lastly,this allows you to meet the 120-day application-to-har-vest safety rule.

If you use sheet composting, poultry waste willneed to be stockpiled after regular coop cleaningsand held until fall. In reality, the waste may as wellbe composted in piles rather than stockpiled toprevent odor and fly issues.

Managing waste to optimize the composting processProper poultry waste management begins in thecoop. Poultry houses should have adequate ventilationto allow the moisture in the manure to evaporate.This not only reduces odors and provides healthierconditions for the birds, but also reduces the over-all weight of the litter, making it easier to lift andremove from the coop.

Routine cleaning of the chicken coop is the nextstep in managing waste. The frequency of cleaningpoultry housing has a direct effect on the nutrientcontent of composted litter. Frequency of cleaningaffects the end ratios of manure to bedding, theend total nutrient content, and the biologicalprocesses that take place during composting.

The frequency of cleaning poultry housingdepends on the number of birds inside and thesize of the coop area. Having fewer chickens or alarger coop area results in less waste buildup,while a higher number of chickens in a smallerarea will create conditions that require cleaningmore often. Although cleaning is best scheduledbased on the amount and composition of the litter,it is expected that a heavily populated coop areawill need to be cleaned every 2 weeks, while aless-populated space will be able to go withoutcleaning for around 3 to 4 weeks.

After cleaning, bedding should be applied as a 2- to 3-inch layer on the coop floor. This providesbetter living conditions for the birds while alsomixing manure with bedding to create a superiorlitter mixture for the composting process.Bedding sources may include wheat or barleystraw, grass hay, alfalfa hay, and pine shavings.

Poultry litter that is going to be composted shouldhave a ratio of manure to bedding anywhere from20:80 to 40:60. If you schedule coop cleaning sothat the litter has 20% to 40% manure and 80% to60% bedding (the preferred method ofmanagement), this may alter the rule-of-thumbcleaning schedule recommended above.

Figure 2. Fully composted poultry litter.

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How poultry litter makeup impacts compostingThe amount of manure relative to the amount ofbedding in the litter influences the biologicalprocesses that take place during composting, thenutrient content in the final compost, and the quantityof potentially damaging salts that the compost couldcontain. Dry straw, hay, and other bedding productsare great sources of carbon, which in the compostingprocess is needed to help balance the high nitrogencontent of poultry manure.

Compost made from a mixture of straw and poultrymanure that is 75% straw and 25% manure has lessavailable nitrogen than the reverse mixture of 25%straw and 75% manure. An excessively high propor-tion of bedding in the litter (more than 80 percent) cancause problems during composting. The low levels ofnitrogen relative to carbon in the mixture will reducebacterial activity and slow the composting process.

If litter containing a high percentage of bedding isapplied directly to the garden, rather than composted,less nitrogen may be available for plant growth duringdecomposition of the litter, which can cause nutrientdeficiencies during the critical early growing season.Once the composting or decomposition process iscomplete, the bound-up nitrogen will be available foruse by plants in your garden.

To avoid problems with low nitrogen content, seekor create an ideal litter composition that requires noadditions or modifications before starting thecomposting process. Such a mixture has a ratio ofapproximately 25 percent manure to 75 percentbedding. For photographs that will help with visualizingmanure to bedding percentages see figures 3–7. Forinformation on carbon to nitrogen ratios in compostingsee the University of Idaho Extension publicationComposting at Home.

Figure 3. Poultry litter that is almost 100% dry poultry manure.This litter has a very high nutrient and salt content and shouldbe applied to the garden in minimal amounts to prevent plantdamage. Adding bedding that is high in carbon will help toreduce the overall nitrogen concentration.

Figure 5. Poultry litter consisting of 50% to 75% manure. Thismixture would probably compost without major issues, but itwould compost better with added straw, hay, or dry leaves.

Figure 6. Poultry litter consisting of 25% to 50% dry manure.This is within the ideal range, but the lower end of the rangeis preferable.

Figure 7. Poultry litter with less than 25% dry manure. Wastewith around 25% manure is a very good starting material inthe production of high-quality compost for garden use.

Figure 4. Poultry litter consisting of more than 75% dry poultrymanure. This litter is still too high in manure to compost properly.

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Using composted litter in the gardenComposted poultry litter is a natural slow-releasefertilizer. One application tilled into the top 6 to 10inches of soil will provide a nutrient source for plantroots and feed them throughout the growing season.

Poultry compost not only supplies nutrients to plants,but also gives many other benefits to the garden. Inmany parts of Idaho the soils are compacted (havepoor soil structure), mostly mineral, very calcareous,and contain little organic matter (figure 8).

Adding composted poultry litter to a garden soilimproves the soil’s structure, overall health, water-hold-ing capacity, and nutrient availability. By improvingthese soil characteristics, our landscapes and gardenscan be healthier and more productive. Soils enhancedwith poultry compost will have a darker color, be lesscompacted, and grow healthier plants compared withunimproved native soils (figures 9 and 10).

There is no exact formula for computing the appropriateamount of poultry litter to apply to a garden orlandscape. The amount to apply depends on whether thelitter is raw or composted and on the ratio of poultrymanure to bedding in the pre-composted litter.

Application ratesAs the ratio of manure to bedding differs from onecompost batch to the next—and consequently eachbatch differs in total nutrient content—it is difficult toidentify the exact amount of available nutrients in eachbatch. For this reason it is also difficult to pinpoint anexact numerical amount of compost to apply in agarden to meet plant nutrient demands. If you want tobe precise in determining application values, youcan send compost samples to a reputable lab fornutrient analysis. If exact calculations are not aconcern, you can make approximate applications ofcompost based on values in table 1.

1Perennials, shrubs, trees, and low nitrogen usage vegetables (carrots,peas, beans, radishes).2Corn, cole crops, onions, garlic, peppers, eggplant, annual flowers, andvine crops.

Low-nutrientrequirementcrops1

High-nutrientrequirementcrops2

Poultry litter containing little bedding 0.5 inches 1.5 inches

Poultry litter containing 50% or more bedding 1.5 inches 3.0 inches

Table 1. Application rates for composted poultry littercontaining different levels of bedding.

Figure 9. Soil improved with one application of poultry litterusing the sheet method after 5 months.

Figure 10. Soil improved with two applications of poultry litterusing the sheet method 1 1⁄2 years after the first applicationand 6 months after the second.

Figure 8. Example of a soil low in organic matter. The soil hasa light calcareous color.

Over repeated years of compost applications, you maywant to reduce the rates at which you apply raw litter inthe fall or composted material in the spring below thelevels indicated in table 1. This will prevent a buildup ofexcessive nutrients that previous crops have not used.Be watchful of plant growth and production habits, andadjust your application rates as experience dictates.

Salt injuryPoultry manure naturally has a high salt content, and ifapplied in its raw form in the spring just prior toplanting it can burn and damage seedlings (problemsover and above the safety concerns). Fall application ofraw litter will help to leach away many of thesedamaging salts. However, if spring application is youronly option, use only composted litter and incorporatethe compost as deeply (6 to 10 inches) as possible intothe soil profile to help reduce the potential for saltdamage.

Although you may attempt to standardize manurecontent in poultry litter, the ratios of bedding tomanure will still vary from batch to batch. Knowingthis should influence your decision as to how muchcompost or raw litter to apply to the garden. Higherratios of manure to bedding in the compost increasethe potential for salt injury. Therefore, compost con-sisting of high levels of manure should be applied atlower rates. For example, mixes made up of 70%bedding and 30% poultry manure could be applied at ahigher rate than a compost mix of 60% poultry manureand 40% bedding.

Nitrogen burning (overfertilization)Raw poultry litter that is fresh, wet, and not compostedwill contain a higher quantity of nitrogen in the form ofammonia nitrogen. If this litter is immediately appliedand tilled into the soil, much of the ammonia nitrogencould be trapped and converted into organic nitrogen.This will increase the damage potential of the alreadysalty litter, resulting in conditions that will either notallow seedling growth or will cause plants to burn astheir roots expand and start to pull in the excessivenitrogen and other salts. This is another reason thatraw manure application is the least preferred methodof application. It is safer from a nutrient standpoint toapply dry poultry litter through the sheet compostingprocess or to use finished dry compost.

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© 2013 by the University of Idaho

Issued in furtherance of cooperative extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, in cooperation with theU.S. Department of Agriculture, Charlotte V. Eberlein, Director of University of Idaho Extension, University of Idaho, Moscow, Idaho 83844. The Univer-sity of Idaho provides equal opportunity in education and employment on the basis of race, color, national origin, religion, sex, sexual orientation, age,disability, or status as a disabled veteran or Vietnam-era veteran, as required by state and federal laws.

Published May 2013

The authors — Lance Ellis, Extension Educator,University of Idaho Extension, Fremont County;Stephen Love, Community Horticulture Specialist,Aberdeen Research and Extension Center, Universityof Idaho; Amber Moore, Soil Specialist, Twin FallsResearch and Extension Center, University of Idaho;Mario E. de Haro-Martí, Extension Educator, Univer-sity of Idaho Extension, Gooding County.

Photos — Figure 1 by Mario E. de Haro-Martí. Allothers by Lance Ellis.

Further readingHart, J., and McNeilam, R. 2000. Fertilizing your garden:

Vegetables, fruits, and ornamentals. EC 1503. OregonState University Extension Service.

Kersbergen, R. 2008. Guidelines for using manure on veg-etable gardens. Bulletin 2510. University of MaineCooperative Extension. http://umaine.edu/publications/2510e/

Mitchell, C. C., and Donald, J. O. 1995. The value and useof poultry manures as fertilizer. Circular ANR-244. Ala-bama Cooperative Extension System.

Rosen, C. J., and Bierman, P. M. 2005. Using manure andcompost as nutrient sources for vegetable crops.M1192. University of Minnesota Extension.

Rynk, R., and Colt, M. 1997. Composting at home. CIS 1066.University of Idaho Extension.

Tyler, R., Hollyer, J., and The Composting Council, Univer-sity of Hawaii. 1996. Compost: It’s a natural! Bethesda,MD: The Composting Council.

Washington State University King County Extension.2010. Using manure, including chicken manure, ascompost.http://county.wsu.edu/king/gardening/mg/factsheets/Fact%20Sheets/Using%20Manure%20as%20Compost.pdf

Zublena, J. P. 1993. Soil facts: Poultry manure as a fertil-izer source. AG-439-5. North Carolina CooperativeExtension Service.