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Chicken manure compost improves soil’s physical and chemical characteristics and is a good fertilizer source for crop production.
Due to its high nitrogen content, chicken manure composts faster than traditional plant-based piles. Chicken manure compost piles must be well managed to ensure high temperatures are achieved needed to kill the pathogens associated with chicken manure.
What is Special About Chicken Manure Compost?
Every six months, in addition to its approximately 180 eggs, a chicken produces about 7.5 gallons of litter (34 dm3), which soon accumulates if there are multiple hens.
Ten hens will produce three-quarters of a cubic yard of waste per year (0.57m3).
Chicken manure and the related litter are richer in organic matter than other manures. They include higher levels of nitrogen, potassium, phosphorus, and calcium.
High in nitrogen, chicken litter can be composted in five to six weeks. Composting lowers the ammonia level, which prevents it from burning plants. Additionally, it lessens the pile’s overall size, weight, and stink.
Composting also helps stabilize nutrients, gradually releasing essential nutrients into your beds over several years.
Finally, the high temperatures produced during the composting process will kill most pathogens and weed seeds.
What you Need to Create Chicken Manure Compost
To create good chicken letter compost, you will need the following ingredients, tools, and facilities:
- Minimally, a cubic yard of chicken pen litter.
- Two cubic yard-sized bins, preferably insulated from the outside elements. This can be made from pallets or cinder blocks. Check out my video on how to do it. The second bin makes it easier to turn the batch.
- A long thermometer – at least a two-foot long sensor to allow you to measure the batch’s center temperature.
- A pitchfork to turn the batch.
- Ready access to water.
- Core strength – needed to turn the batch. It’s quite a workout!
Compost Chicken Manure Temperatures
Things heat up when we combine nitrogen, carbon materials, air, and water in a closed environment. This is due to chemical reactions caused by different microorganisms (bacteria, fungi, actinomycetes) consuming nitrogen and carbon.
Typically, mesophile organisms are involved in the initial decomposition and survive the first heat spike that may reach temperatures of 113⁰F (45⁰C) during the first two to eight days.
This first activity salvo lowers the pH of the mixture due to the production of organic acids.
Thermophile organisms push temperatures above 113⁰F (45 °C), replacing some mesophilic microorganisms.
Thermophiles break down more complex carbon sources, such as cellulose and lignin, transform nitrogen into ammonia, and boost the mixture’s pH (more alkaline).
As temperatures rise above 140⁰F (60⁰C), spore-producing bacteria and actinomycetes appear, allowing the humus to smell like earth.
These two bacteria break down waxes, hemicelluloses, and more complex proteins.
During this phase, the mixture must be frequently ventilated to supply oxygen to the microorganisms so they can continue the decomposition process.
Organic Composting Note:
Organic operations must meet specific temperature and turning frequency requirements. The Organic Materials Review Institute requires compost that includes animal materials to reach and maintain temperatures of 131 – 170⁰F (55 – 77⁰C) for 15 days and piles to be turned at least five times during those 15 days.
This temperature is enough to kill most human and animal pathogens except Listeria monocytogenes, Clostridium perfringens, and Clostridium botulinum.
Noting Chicken Manure Compost Risks
While it’s great to note that using chicken manure compost effectively introduces essential slow-release nutrients into your garden beds, it would be irresponsible not to emphasize that some safety measures are required.
According to the University of Nevada:
Whether composted or aged, manure should be applied no later than 90 days before harvest of non-ground-contact crops, such as trellised tomatoes, cucumbers, and peppers; and no later than 120 days before harvest of ground-contact crops, such as lettuce, strawberries, and carrots.
How to Compost Chicken Litter
Chicken litter can have a carbon-to-nitrogen ratio of anything between 6:1 to 25:1 – depending on the balance of manure to pen litter. Our target is anything between 25:1 and 35:1.
You should adjust ratios if your letter has a high fowl feces content. Let’s use Pearson’s square method.
The Pearson Square Method allows us to determine how much straw must be added to a manure-based mix like chicken litter. The starting point is the three known values:
- The guestimated C: N ratio of our chicken litter: is 20:1 (depending on the litter-to-poop ratio)
- The C: N ratio of straw: 80:1
- The C: N ratio desired: 30:1
Given the above, we can calculate three values:
- The carbon difference between the chicken letter and the straw: 80 minus 20 = 60
- The chicken litter percentage of the mix = difference between its carbon ratio (20) and that of the target ratio (30), i.e., ten expressed as a percentage of the difference between the two additives (straw and chicken litter). 10/60 = 16.67%
- The straw needed if our chicken litter has a 20:1 carbon-to-nitrogen ratio is the remaining 83.3% (100 – 16.67).
- Mix the straw and chicken manure, slash litter, in the bin, wetting it amply.
- From day two, start measuring the core’s temperature, turning it when it has reached 113⁰F (45⁰C). Move the batch to the adjacent bin, incorporating the outside material into the center.
- Make sure moisture levels are around 50%. Measure this by squeezing a handful. If the water flows out from your hand, it’s too wet (add some hay). If there isn’t a drop between your fingers, it’s too dry (add more water and keep testing).
- Take daily temperature measurements, turning the batch every time it peaks near 170⁰F (77⁰C)
- Each successive turn, the temperature will be lower, or the time to reach a temperature above 131⁰F (55⁰C) will take longer. This is normal as the batch matures.
- Keep the batch covered once temperatures no longer reach thermophilic temperatures, and allow it to cure before use.
I hope that helps you speed up your process of creating what your soil longs for.