What is Composting?
Composting is a highly energy-filled activity that transforms all the biodegradable organic matter into humus-rich compost.
There is already a lot of stored energy in the organic material set aside and heaped up for composting. It gets all its energy from the sun when the solar energy gets transformed into chemical energy during photosynthesis. This chemical energy is either consumed by the micro-organisms when the chemical bonds break or escape as heat when the composting activity starts. The micro-organisms first break down the organic material into simple compounds and then reform them into ‘new complex compounds’.
This is what ultimately changes how the composting material looks. A huge reduction in mass and volume occurs as CO2 and water vapours evaporate. If you keep a watch on the changes happening in a pile at every stage,
you will see fresh food waste turning dark brown first and then black. No trace of green, red, white, orange or yellow is visible anymore.
Not just the look, the texture or the smell of the material, the very nature of it changes beyond recognition. The C:N ratio decreases, pH neutralises, the amount of humus increases and the exchange capacity of the material increases. Uniformity in colour and crumbly texture begins to emerge as the biological activity begins to ebb away and the energy that was so visible during the active phase of composting begins to mellow. All the energy is now stored in the compost and the microbes that are still alive and busy breaking down stubborn substances like woody materials which are high in lignins.
An excerpt from ‘Endlessly Green: Solid Waste Management for Everyone’. Page 200-201.
Why is Composting Necessary?
Because all the available biodegradable material coming from plants or animals is not in a form that the plants can consume and process for survival. It needs to be broken down first to a point where all the nutrition embedded in it is transformed into a form which the plants can easily absorb and assimilate.
Now, let us look at what actually happens during the process. According to Robert Rynk et al., the definition goes thus: “During composting, the microorganisms consume oxygen (O2) while
feeding on organic matter. Active composting generates considerable heat, and large quantities of carbon dioxide (CO2) and water vapour are released into the air. CO2 and water losses can amount to half the weight of the initial materials. Composting thus reduces both the volume and mass of the raw materials while transforming them into a valuable soil conditioner.”
An excerpt from ‘Endlessly Green: Solid Waste Management for Everyone’, Page 153.
A Little About C:N Ratio
This is the most fundamental aspect of composting. If you don’t get this right, then everything falls apart.
When it comes to getting carbon:nitrogen right, the most tried-and-tested ratio has been 3:1. That means, three part of kitchen waste to 1 part of cocopeat. You can also add a few handfuls of dry leaves, if you have. Mixing the ingredients fetches faster results than layering as it helps the microbes invades the food surface without delay.
You can also compost using only dry leaves. Crushed dry leaves work better. Mix 50% old compost and 50% crushed dry leaves and mix these two with three measures of kitchen waste (preferably shredded). This will help you get things going quickly. If not, you will face issues with excess maggots, bad odour, low temperature in the pile, etc. To fix these issues, check out the Troubleshooting section below.
More info available in ‘Endlessly Green: Solid Waste Management for Everyone’, Page#: 163.
What's In & What's Out
Segregation!
This is the ABC of SWM.
Separating kitchen waste right at the source is the foolproof formula that ensures quality compost as it is not mixed with hazardous materials like plastic, e-waste or sanitary waste.
After you segregate the waste, do remember to avoid adding liquids like sambar, rasam or oil residues (it’s fine if it is in small quantities which you can mop up using a tissue paper or any kind of flour, but it should not be in large quantities). Avoid coconut shells as they take too long to decompose. You can add the rest of the rejects that comes out of your kitchen including nonvegetarian leftovers.
Get Your C:N Ratio right
This is the most fundamental aspect of composting. If you don’t get this right, then everything falls apart.
When it comes to getting carbon:nitrogen right, the most tried-and-tested ratio has been 3:1. That means, three part of kitchen waste to 1 part of cocopeat. You can also add a few handfuls of dry leaves, if you have. Mixing the ingredients fetches faster results than layering as it helps the microbes invades the food surface without delay.
You can also compost using only dry leaves. Crushed dry leaves work better. Mix 50% old compost and 50% crushed dry leaves and mix these two with three measures of kitchen waste (preferably shredded). This will help you get things going quickly. If not, you will face issues with excess maggots, bad odour, low temperature in the pile, etc. To fix these issues, check out the Troubleshooting section below.
More info available in ‘Endlessly Green: Solid Waste Management for Everyone’, Page#: 163.
The 3 Phases of Composting
Composting is an incredibly complex algorithm designed by Mother Nature. It is happening all around us whether we pay heed to it or not.
Ever wondered why an ice cream box frozen at subzero conditions goes stale and begins to smell bad? It’s actually the presence of anaerobes that thrive even at -2°C. Micro-organisms can be present at extreme temperatures: At -2 °C, and also at 122 °C.
Composting is a highly intricate process. The standard procedure takes anything between 30-45 days depending on the accelerators involved. A whole lot of work has to be done by different strains of bacteria and fungi to transform the organic material into compost.
Although reams can be written about this beautiful process without which life is impossible on this planet, here’s just the gist of it. Click HERE.
Some Need-To-Knows
When it comes to the science of composting, it is very important to understand these three aspects: Temperature, pH levels and electrical conductivity, or salt content.
TEMPERATURE: The maximum rate of degradation takes place in the 45°C–55°C range and conditions outside this range are sub-optimal. If your pile maintains this temperature, then that’s enough.
pH LEVELS: Just. Do. Not. Bother! Because regardless of the pH of the starting materials, composting yields an end product with a stable pH that is close to neutral.
ELECTRICAL CONDUCTIVITY: Make sure you buy cocopeat which is low in EC. Otherwise, composting process gets affected and so does the output.
The Grand Finale!
The best way to figure out whether your composting pile is ready for harvesting is by putting your olfactory senses to work. If you are able to detect earthy fragrance, usually referred to as petrichor, then the first stage of composting is about to be over.
To be on safer side, it is always better to leave the bin undisturbed for at least 4-5 weeks instead of harvesting the pile prematurely which can trigger issues. Only then comes the curing part which is the second stage of composting. Harvesting is fun. It feels like a reward!
After Composting...
The best way to figure out whether your composting pile is ready for harvesting is by putting your olfactory senses to work. If you are able to detect earthy fragrance, usually referred to as petrichor, then the first stage of composting is about to be over.
To be on safer side, it is always better to leave the bin undisturbed for at least 4-5 weeks instead of harvesting the pile prematurely which can trigger issues. Only then comes the curing part.
The Next Part of The Story
Most people don’t know the difference between compost and humus. No wonder they fail to give equal attention to the curing stage when humus formation happens. The first stage is all about energy-filled breakdown process. The second stage is all about curing.
Set aside your compost for curing, preferably after sieving. If you have large plants or trees, feed the larger clumps directly or add them to the next batch. Let the finer compost stay for a month or more. This is when soil-friendly microbes begin to find home.
Let's Reap All Those 4 Ms
The simple act of turning your kitchen and garden waste can build an endless positive cycle around you and way beyond. Compost means microbes. It provides moisture to your plants, thanks to its spongy texture thereby bringing down water consumption level gradually.
Compost can act like a mulching agent and keep the root zone and microbial population protected from harsh sunlight. Compost also means organic matter which the microbes need in abundance to keep themselves alive and kicking. These four Ms are at the bottom of all forms of holistic farming.
Let's Fix Those Bugs - 1
Bad odour during composting is one of the most common and annoying issues for many. Learn how to fix it. Similarly, low temperature is often the result of poorly put-together inputs without giving a thought to the C:N ratio.
Although maggots are the most essential physical decomposers in the composting pile, you can’t have them popping out of your composter in big numbers. Here’s how to fix the excess proliferation.
Let's Fix Those Bugs - 2
A closed composter can tackle flies. But make sure your composter also has enough aeration. Always cover the top layer with dry leaves or cocopeat. Excess tea purely depends on the nature of contents. Make sure you drain out the tea and feed it to your plants at 1:30 (tea:water) ratio.
Most people think composting is a dirty affair and hence bacterial or fungal infections are a given. That may not be entirely true. Maintain hygiene around your composter and pay attention to C:N ratio so that heat builds up properly which will eventually keep pathogens in check.