Composting – Why it’s Important and 4 Top Tips!

Here at Ocean Mimic we spend a lot of time talking about plastic waste and its impact on our oceans. However, as it’s International Compost Awareness Week this week we decided to dig into organic waste and composting instead.

We wanted to understand more about the issues surrounding organic waste, the main disposal methods and their links to the climate crisis. We’ll also be exploring how you can help reduce waste and sharing some composting tips too …

Firstly, some background on organic waste.

When we refer to organic waste we’re talking about any waste that is capable of undergoing anaerobic or aerobic decomposition. For example food waste, garden waste and paper / cardboard waste.

According to World Bank, on average it is estimated that organic waste accounts for 56% of total municipal waste in low-income countries, 53% in middle income countries, and 32% in high income countries.

Of all the waste produced in Bali in particular it is estimated over 60% is organic waste. We know that plastic pollution is a problem in waterways and oceans all around the world, but organic waste is also a big polluter and can be harmful to the environment and locals alike. It can contribute to flooding, release toxins into the environment and upset the natural balance of soil and water etc.

organic and plastic waste polluting rivers in Bali
Just a selection of images showing organic waste polluting the rivers of Bali.
Photo credit : Sungaiwatch

This is before organic waste even makes it to a disposal plant / location!

Current most common disposal methods:

Organic waste usually ends up on landfills or is incinerated to make energy. Neither of these options are great for the environment or our health …


In landfills, organic waste undergoes anaerobic decomposition (because of the lack of oxygen) and makes methane. Methane is a damaging greenhouse gas that is contributing to the climate crisis and is 25 times more potent than carbon dioxide!

Not only are we actually running out of space for landfills, but they have been found to negatively damage the environment and health of the people who live near them. They can cause issues ranging from mild irritation to eyes and skin to life threatening cancer and birth problems in humans. They have been associated with a loss of biodiversity in surrounding areas and are known to leach toxic chemicals into the surrounding soil and water systems!


Incinerators basically burn waste and in the process produce energy. Not only does this method stop resources and nutrients from being recycled / reused, but this method also emits greenhouse gasses, this time in the form of CO2. It also seems that incinerators may actually release more CO2 per unit of electricity than other types of power plants!

As well as CO2 this burning process also releases toxic chemicals like lead, mercury, dioxins and acid gases that have been linked to various health hazards. These health hazards range from respiratory problems and increased cancer rates to neurological problems and reproductive disfunction.

Given that over 80 countries have committed to reduce emissions as part of the Paris Agreement and given the other associated health and environmental issues raised, it seems improving waste management should be high on the agenda! Don’t get us wrong, it is a hot topic and there have been improvements, but more can be done here!

There are many schemes that are looking to make organic waste more useful and less harmful (e.g. biofuel), but these are usually cost prohibitive in many locations and have to compete with other fundamental needs (like water supply and health care etc.).

So, what can YOU do?

It’s been estimated that 6%-8% of all human-caused greenhouse gas emissions could be reduced if we stop wasting food. So here are a few tips to help with this:

  1. Try to plan ahead and be smart with your purchase decisions. Oh, and don’t shop when you’re hungry!
  2. Make the most of your freezer. Buy frozen alternatives or find ways of freezing fresh items for later uses. For example, blend your wilting fresh herbs with olive oil and freeze in an ice cube tray.
  3. Composting is also a great option – Composting diverts waste from landfill and therefore reduces methane emissions. In fact home composting has the potential to divert up to 150kg of food waste per household annually!
definition of composting - the act of collecting and storing plant material so it can decay and be added to soil to improve its quality

Some of you might be lucky enough to have kerb side compost collection in your area (please do check with your local council and services), in which case only tips 2 & 3 apply to you. However, for those of you who don’t, could you start composting in your garden?

Here are some composting tips to think about:

1. Organise the right set up and regularly monitor progress:

  • Pick your spot carefully – you want a flat, well drained area that the worms can easily access. Ideally pick a spot removed from buildings, just in case.
  • Remember to turn your compost regularly to help it aerate. Every few weeks is good.
  • The right temperature can also make all the difference. There are slightly different schools of thought here, but keeping it between 140-150°F / 60 – 65°C should be good. Not too cold so that you risk contamination, but not too hot for the bacteria you need.
  • Water your compost in dry weather – you want it to be damp, but not soggy

2. Put the right stuff in your compost:

  • Vegetable peelings, fruit waste, plant pruning and grass cuttings are all great additions to compost. They are fast to breakdown and provide vital moisture and nitrogen.
  • Egg shells will add calcium to your final composition, which helps plants build cell walls. You can choose to crush them or not (crushed will compost quicker).
  • Cardboard, scrunched paper and leaves are slower to decompose, but are good for providing fibre and air pockets within the heap (remember oxygen is good).
  • Worms love coffee grounds and your compost needs worms, so definitely include if you can.

3. Know what you can’t compost:

  • Avoid coal ash as it contains sulphur and iron that can damage plants.
  • Don’t add meat, bones, fish, fats/oils or dairy – they can cause it to smell and also attract pests! Apparently they can also cause the heap to overheat which could kill off the bacteria we need.
  • Some also suggest not adding rice (cooked or otherwise) or pasta. They can attract pests and cooked rice in particular can lead to the growth of unwanted bacteria.
  • No inorganic material. In our opinion it is also best to avoid adding bioplastics as they usually need industrial scale composting conditions to break down. Read : Bioplastics : Eco Friendly or Scam for more on this.

Note that local guidelines can vary if you have kerb side pick up, so please check details with them.

3 different composting bins
Composting can take many different forms!

4. Remember it’s a balancing act, but all will be good in the end!

  • The microbes that break down the compost pile need both nitrogen and carbon. So be sure to get a good mix of green (e.g. food scraps and grass clippings) and brown (e.g. dead leaves and paper) waste. Green waste = nitrogen and brown waste = carbon.
  • You can make adjustments as you go and try different things to see what works for you. Even if you mess up, eventually you’ll get usable compost. It’s just a matter of time!
  • You’ll know you have usable compost when you can’t recognise anything you put in there. It’ll look like a rich dark soil.

Finally composting can be educational for all ages, so be sure to get the kids involved too! 

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