The Process of Composting

Reader Contribution by Erik Thiel

Compost happens, yes. But if food scraps are thrown into a pile and left to rot, a hot smelly mess may be taking over. That’s because the process of composting is a symbiotic relationship between carbon and nitrogen. Or at our home, cardboard and food scraps.

In order to end up with a pile of black, crumbly, rich scented, compost filled with fully charged micro-organisms capable of generating life-giving forces willing to build soil fertility worthy of growing nutritious veggies, one must understand the role of carbon and nitrogen. At least a little.

Carbon and Nitrogen Ratios

The right combination of carbon and nitrogen will please the micro-organisms responsible for creating the compost gardeners dream of. That’s because these two elements form the basis of their diet. Carbon gives them energy, while nitrogen gives them everything to grow cells and function.

Figuring out how much carbon material and how much nitrogen material to add does not have to be rocket science. One answer for the correct carbon to nitrogen ratio is as follows: 30:1. (I find that confusing.) Another answer can be 10-gallons carbon material to 5-gallons nitrogen material.

An even simpler answer? For every 5-gallon bucket of food scraps added to the compost pile, also add one 5-gallon bucket worth of cardboard pieces. Then go from there.

Before going there, let’s first identify some specific forms of carbon and nitrogen material. According to Compost Chemistry from Cornell University:

In general, materials that are green and moist tend to be high in nitrogen, and those that are brown and dry are high in carbon. High nitrogen materials include grass clippings, plant cuttings, and fruit and vegetable scraps. Brown or woody materials such as autumn leaves, wood chips, sawdust, and shredded paper are high in carbon.

Once the process of composting is started, it becomes easy to tell if the compost pile needs more cardboard or more food scraps. If it smells horrible, it needs more cardboard. If it seems to not be doing much, it needs more food scraps.

According to Cornell University, if there is too much nitrogen it will be lost as ammonia gas – that horrible smell. If there is too much carbon, there will not be enough nitrogen to supply cell growth and functioning to the micro-organisms who need it to make compost. That means they won’t make compost. A lack of nitrogen will also not allow the compost pile to heat up correctly, which reminds me … there are a few more things worth mentioning about the process of composting.

Temperature, Dimensions, and Oxygen

Temperature and dimensions basically go together. According to the Encyclopedia of Gardening by the American Horticultural Society:

To heat up efficiently, a compost pile should be at least one cubic yard (1 cubic meter) in size, but 2 cubic yards is preferable. Compost reaches its maximum temperature in two or three weeks and matures in about three months. Turning the pile speeds up the process and ensures complete breakdown.

Not enough oxygen will also produce a horrible smell. That’s why it’s important to turn the compost pile with a pitchfork every now and then, especially when adding more carbon materials to cover up existing odors.

At Our Home

Once our saved food scraps and coffee grounds exit the front door, they are stored in a 5-gallon bucket secured with a lid. When that bucket is filled, it’s dumped on the compost pile. About 5-gallons of cardboard is then layered over the food scraps. I don’t do too much turning to be honest. Once a month or so.

I do keep it moist if it looks too dry and I like to keep a tarp over the top. I’m not afraid to let the pile give off a slight aroma because I don’t want to add too much cardboard and slow down the composting process. Once I do smell a slight foulness, I add more cardboard and turn it with the pitchfork.

My biggest concern is keeping the neighbors happy. They both gave me the thumbs up to compost in the front yard. Two thumbs-up and a smile right back. And as-of-date, there have not been any complaints about residents composting in the history of this town. It can stay that way.

The worse thing that can possibly go wrong in the process of composting is to fail by not trying to compost. Remember, compost happens.