In recent months with all of us spending more time at home and cooking more, one of the many ways we can live more sustainably is reducing our food waste in a natural way. Composting is the most efficient way to get creative in our low or zero waste journey, and it’s one that is easily available to all of us. Composting is essentially nature’s way of recycling organic matter; where the vegetable scraps decompose itself to re-nurture the soil and thus completing the entire lifecycle of the ecosystem.
What exactly is composting and why does it matter?
Composting in scientific terms is a ratio of Nitrogen and Carbon, which serves as the home to billions of micro-organisms such as bacteria, fungi, and actinomycetes. In a compost bin, microbes use air and water to break down organic matter into nutrition-rich dirt. The Nitrogen comes from all the kitchen green wastes like fruit peels, cut-offs or veggies that have gone bad and can’t be eaten anymore. Carbon, on the other hand, comes from dry materials like leaves, cardboard or newspaper. By mixing the carbon and nitrogen (ideally in a 30: 1 ratio), the microbes become active and start multiplying and breaking down the ingredients. This form of composting is also called aerobic composting.
With fruit scraps, papers and cardboard making up a big part of what we throw at home, composting is a very effective way to significantly reduce our domestic waste, while also producing a nutrient-rich cocktail to fertilize our plants in the process.
A simple way to start your own aerobic home compost:
It took me a little while before I started composting and I often feel; I should have started it sooner. Here is a simple way for you to get started. My personal advice to you would be not to get too concerned about getting each step exactly right. Instead, just give it a try as I can assure you, you will figure it out as you go!
Preparation – What you need to get started:
- Reuse a plastic bucket / mud pot / big drum or buy a compost bin at The Green Collective or homeware supply stores. Any size is good, just make sure it’s not too small. I got mine online from Lazada (I wanted to see how a Lid filter works with only holes above and it has been working well so far)
- Make some holes into the container on the side and above on the lid
- Collect some Carbon: Dry leaves from the park, newspapers, or torn cardboard eg. from delivery boxes or toilet rolls, sawdust.
- Collect some Nitrogen: ie. vegetable /fruit scraps and cuttings (The freezer is a great way to store them in an odour-free way)
- Use a bit of soil to enrich your compost with microorganisms
- When available, use coco peat and buttermilk
- Put aside some water
The Compost Making Process – How it works:
- When it comes to this composting method, the amount of air circulating through the pile has a direct effect on how the pile functions. That’s why it is very important to have a well-ventilated bin.
- The aim is to layer Carbon and Nitrogen into the bin. The ideal C: N ratio for composting is generally around 30:1, or 30 parts carbon for each part nitrogen which simply means much more dry leaves and cardboard than kitchen waste.
- The first step is to place your Carbon into the bottom of the bin.
- The second layer is your Nitrogens. To speed up the process, it’s best to shred or cut them into small pieces.
- For the first time round, to add some microbes to your bin, you can either add 2 spoons of buttermilk (or yoghurt mixed with water) or some soil found in your garden or nearby park.
- Completely cover your Nitrogens with Carbon materials.
- Each time you add Nitrogen to your pile, cover them with Carbon. Do not let any greens show, else you pile may attract pests.
- Repeat the process of alternating the layers of Nitrogen and Carbon every day until the bin is full.
- Every week: do turn your pile to give some air and add some water for moisture (if needed) to help compost faster.
- When the compost is ready, which takes anywhere from 5-9 weeks, it should look and smell like rich dark mud. There should not be any visible bits of food scraps or carbon pieces in it.
- As each of the ingredients added to the bin take a different time to decompose, the general rule of thumb, the smaller the size you add them, the faster the progress.
What can go wrong and how to fix it:
- Compost has a reputation for being smelly. This is usually the case when the pile is off-balance and has more Nitrogen than Carbon or has too little oxygen. Adding Carbon and air will usually fix this issue.
- Blackflies -If we have too much Nitrogen and not enough Carbon in the pile, the compost may become breeding ground for house or soldier flies. To solve this issue, again simply add more Carbon and we can also cover a net-like material (ie. onion or potato bag net) or a thin layer cloth with the lid. A properly managed compost bin will not attract pests or rodents and will not smell bad.
- White worm-like creatures which are called Maggots. These can be present which is okay as they help in decomposition. I let them be as they help to get the job done.
- The pile should neither be soggy nor too dry, it should be moist.
- Do not leave it in the rain or in the hot sun. If the pile gets too hot, it will kill the microbes as a result. Do keep it in a cool shady area.
What you can add to the compost:
Carbon sources: Leaves, sawdust, ash, coconut husk, hay, cardboard, newspaper, toilet/kitchen rolls, crushed eggshells, wood chips
Nitrogen sources: Fruit and veggie peels and cuttings, grass clippings, manure, old rice or pasta (wash to remove spices and oil), coffee grounds.
What alternatives do you have to aerobic home composting?
In this method, a special bacterium is mixed into your food scraps, triggering to food to break down via fermentation. Bokashi can be done alongside regular composting and typically takes 1-2 months to compost.
In Vermicomposting earthworms are used for the decomposition. While this method might not be for the faint-hearted, it’s actually quite effective and the composting process can take as fast as 2 weeks.
Finding a compost maker in your area
NParks: Composing – Caring for plants.
NUS Blog: Food Waste, Composting and Urban Ecology