Did you know that the beginning of May is when we celebrate all things compost?

International Compost Awareness Week (ICAW) runs from May 1 to 7 and is the largest and most comprehensive education initiative in the compost industry.

Now, you may have heard of composting (and you may even compost yourself), but have you ever thought about why we need to compost and why our food products don't break down efficiently in the landfill?

This year for Compost Awareness Week, let’s dig into what chemical processes are lacking in a landfill versus in a compost system. The more we know, the more we can be inspired to take action by diverting food from the landfill and giving it new life.

What happens in landfills?

Many of us have seen the statistics: that roughly one-third of the food we produce annually is never eaten. Food waste is one problem, but the way we manage it is another story. We assume that when we throw food or plant-based materials into the garbage, they break down within a few years—but the systems in a landfill are far more complex than that. Food is, of course, organic and biodegradable, but it’s the landfill environment that prevents organic materials from decomposing efficiently.

A large assortment of garbage ends up in the landfill, including metals, medications and plastics, all of which can mix with rainfall to create leachates and harmful gasses. In order to prevent these elements from mixing, landfills are built with thick layers of clay and plastic to line, cap and trap the materials within. Sturdier items like plastics will essentially be preserved in this environment and may never break down, but food and plant-based products do break down, and they do so at a cost to the planet.

By creating an environment that is completely sealed off, food is trapped in an “anaerobic environment”, which means that no oxygen can be accessed. Without oxygen, the insects and microorganisms needed to break down the materials properly can’t survive, so food that decomposes in a landfill without air will produce methane, a powerful greenhouse gas that traps over 20 times more heat than carbon dioxide. If these gasses aren’t contained completely by the landfill piping, they can leach into our atmosphere (and they have been, which is a leading contributor of climate change).

This lack of oxygen makes landfills inefficient at breaking down our food, and there's also the issue of other resources being wasted in the process. There is a cost of transporting materials to other countries that manage our waste when space in Canada and the US is at capacity. Landfills are also known to contaminate soil, ground water, and to pollute debris in surrounding areas. Tossing our food scraps in the garbage has been the quick-fix solution for decades, but there’s an alternative that is just as simple, and when done properly, this solution can have a positive impact on our environment rather than a negative one.landfillPhoto by Tom Fisk

What is composting and how does it have a positive impact?

“Isn’t composting just throwing food into a pile and letting it decompose? How is that different from a landfill?” Well, the difference is in the oxygen. A compost pile can breathe. When you compost, the pile is aerobic (versus the landfill’s anaerobic environment), and it’s a key ingredient to breaking down food efficiently and productively.

Compost piles don’t just sit, they are turned either by hand in a home composter, or with machines in a larger operation. On paper, it seems like a complicated process, because it is—for the microbes— but not for us. Our role in composting is to facilitate and create the ideal environment for the bacteria, fungi and microbes to do the work, and all it takes is arranging the right ratio of ingredients for your compost pile.

It’s as simple as following a recipe. Compost is made up of four key ingredients: carbons (brown materials like sawdust, shredded paper, grass clippings), nitrogen (green materials, which are your food scraps and plant material), oxygen (stirring the pile regularly), and water (adding water to make sure the pile doesn’t dry out, but not too much so that the bacteria and fungi suffocate—remember, we want oxygen).

If each of these elements is present in the right proportions, the essential microbes will thrive, multiply and digest the raw materials, create heat within the pile, and very quickly break down the food, leaving us with an earthy-smelling organic material.

The composting process is in itself environmentally beneficial, but then in its final form, compost is also a nutrient-rich organic fertilizer that can be used on farms and in gardens to bring organic matter and life back into our soil. It’s the gift that keeps giving.

Compost eliminates the need for chemical fertilizers in our gardens and it also aids in carbon sequestration and acts as a carbon sink, trapping and containing carbon in the soil rather than in our atmosphere.

When used in soil, compost helps to feed essential microbes and organisms, and finally: us. Because compost helps feed plants essential nutrients (and helps retain water in the soil for the plants), those plants grow and feed us in return. Composting is a beneficial, full-circle operation, and all it takes is making the switch from an anaerobic (no oxygen) environment to an aerobic (full of oxygen) one.

If you’ve been thinking about starting to compost, ICAW is the perfect time to get your pile going or to begin outsourcing your food scraps to a local farm or operation. The simple task of keeping our food scraps out of the landfill instead of composting them does so much good for the environment, all while giving our food “waste” new life.