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In this beginner’s guide to composting, we’ll break down the benefits of composting, what you can compost, and tips to compost at home so you can turn your food waste into nutrient-rich fertiliser.
- What is composting?
- Why should you compost?
- Different types of composting: home vs commercial
- How to compost at home
- What to put in your compost bin
- Compostable packaging
- Understanding composting certifications
- Recycling versus composting
- Biodegradable versus compostable
- Composting in Australia
- How to encourage change in your local council
What is Composting?
Composting is nature’s version of recycling. Organic materials, like food scraps, garden waste and compostable products, are broken down into nutrient-rich soil by microorganisms, such as fungi and bacteria.
Why Should You Compost?
There are so many reasons to compost – for people, soil, plants and the planet at large.
Composting can:
Divert Waste From Landfill
Sending less waste to landfill has both economic and environmental benefits. Imagine if we all saw our waste as a resource! Composting our food and organic leftovers will help recover a resource that would have been wasted in landfill, and instead turn it into a beneficial fertiliser.
Reduce Emissions and Capture Carbon
Organic waste in landfill generates methane, a greenhouse gas that’s on average 28 times more potent than CO2 (source). By composting food waste and other organics instead, we can significantly reduce methane emissions. Not only that, composting actually helps capture more carbon by improving soil health and productivity.
Reduce the Need for Chemical Fertilisers
Composting turns waste into nutrient-rich, natural fertiliser, and this new resource has the potential to reduce the need for chemical fertilisers.
Improve Soil and Agriculture
Composting adds valuable nutrients to the soil. It improves its health, which in turn promotes higher yields of agricultural crops.
Healthy Plants
It’s simple – healthy, nutritious soil grows healthy plants.
Conserve Water
Healthy soils rich in organic matter can retain more water. This can ultimately help reduce the need to water crops.
Prevent Soil Erosion
Compost improves the soil structure, its water-holding capacity, and surrounding plant growth. These all contribute to reducing soil erosion by stabilising the soil and preventing the loss of valuable topsoil from water and wind action.
Reforestation and Restorations
Compost can help aid reforestation, wetland restoration and habitat revitalisation efforts by improving contaminated, compacted and poor-quality soils.
Different Types of Composting – Home vs Commercial
Home Composting
This refers to what’s in your backyard. You can throw things like food scraps, grass clippings and leaves into your home compost and they’ll break down over several months, sometimes years.
Different home composting methods include:
Backyard Composting – the most common method using a traditional compost bin or container in your backyard.
Vermicomposting– also known as a worm farm, this method uses worms to break down organic matter and produce valuable worm excrete castings.
Bokashi Composting – this uses anaerobic fermentation to break down organic matter. Food waste is sealed and fermented with a special mix of bacteria and yeast.
Subpod Composting – a type of vermicomposting, the Subpod is an in-ground compost bin that can create a self-fertilising garden bed!
Commercial Composting
Commercial composting, also called industrial composting, is a controlled setting with specific temperatures and inputs (like water, air, carbon and nitrogen-rich materials). Given it’s a controlled environment, commercial compost will rapidly break down a wide range of organic materials.
Five different commercial composting methods include:
Windrow Composting – the formation of long, narrow rows of organic waste. This method relies on natural sources like sun and wind to break down organic matter.
In-Vessel Composting – the processing of organic waste in enclosed containers or vessels with control over the temperature, moisture and environment.
Insect Processing Units – insect processing units, like GoTerra, use revolutionary modular, autonomous technology powered by insects that consume food waste!
Anaerobic Digestion – this method helps organic matter break down without using oxygen. The end product can then be used in biogas plants to generate renewable energy and organic fertilisers.
Aerated Static Pile (ASP) – this composting method uses a combination of air and microbial activity (like bacteria and fungi) to turn organic waste into compost.
Composting For Beginners – Getting Started
Starting a home compost is easier than you may think.
But first, you should choose a method that suits you best – whether it’s outdoor backyard composting, a worm farm or indoor bokashi composting. Here are some questions to help you choose the right method.
How much organic waste do you produce?
Everyone is different. A big family with lots of food waste may have different composting requirements to a single homeowner. If you have a small amount of kitchen waste, you might opt for bokashi composting because it requires minimal space. If you have a big family, you might opt for a large backyard compost bin.
How much space do you have?
If you live in an apartment with minimal space, you might choose the space-saving bokashi method. Alternatively, if you have a large backyard with enough space, an aerobic composting bin will allow for a lot of kitchen and yard waste.
How much time can you spend composting?
Time commitment can vary between composting methods. A worm farm (vermicompost) is a great choice if you’re busy, as worms do a lot of the work for you! Backyard composting can allow for a lot of food waste, but it can be more involved as you often need to layer it, keep it moist and turn your compost.
Composting Basics – What Goes in a Composting Bin?
What Can You Compost?
- Leaves, grass trimmings, sticks and twigs, weeds that haven’t gone to seed, houseplant trimmings and dead flowers
- Pinecones, pine needles or straw, fallen bird’s nest
- Fruit and vegetables, including peels, rind, pits and corn cobs
- Chilli, onions, garlic and citrus*
- Tea bags (if they’re not made of plastic, always check the label)
- Coffee grounds
- Eggshells and nutshells
- Rice, pasta, bread
- Herbs and spices
- Hair, nails and pet fur
- Pet bedding (i.e. for hamsters and rabbits)
- Unlined paper with minimal printing
- Cardboard and egg cartons (broken into small pieces, remove any labels)
- Toilet paper rolls and paper towels
- Corks and wooden toothpicks
- Wood chips and fireplace ashes
- Certified home compostable packaging, like brown paper lunch bags, coffee cups, bowls and cutlery (always look for the correct home compostable certification – learn more about the certification here)
What Can’t You Compost?
- Fossil-based plastic products
- String
- Aluminium foil
- Dryer and washing machine lint and dust from the vacuum cleaner (this might contain micro-plastics and harmful chemicals)
- Waxed or lined paper and cardboard
- Large twigs and branches
- Pet droppings (especially dogs and cats)
- Cooking fat and oil
- Charcoal ash (BBQ briquettes are
often infused with chemicals) - Dairy, meat and animal products**
Tips
*Chilli, onions, garlic and citrus are suitable for a backyard compost bin, although it’s recommended not to add too much if you have a worm farm – the acidity can negatively impact your worms!
**Animal and meat products can be composted, but it’s not always recommended or you should limit the amount you compost as it may attract pests.
A healthy compost will balance ‘greens’ (nitrogen-rich materials like fruit, vegetables and grass clippings) with ‘browns’ (carbon-rich materials like leaves, twigs, shredded paper and certified home compostable packaging). Aim for one part greens to two parts browns.
What About Compostable Packaging?
Compostable packaging is packaging that has the ability to naturally break down in a composting environment – whether that’s a commercial composting facility or your backyard compost. But it can get a little confusing for consumers – so let’s explore recycling vs composting, biodegradable vs compostable and the different composting certifications.
Recycling Versus Composting
For starters, composting is a form of recycling – organics recycling! The difference? Composting is for organic matter only, and other recycling is for paper, glass and plastics.
Both recycling and composting are great ways to turn waste into something valuable and they both contribute to a zero waste circular economy.
The process you use will depend on the material you’re disposing of and the facilities available in your local area. Check for compostable certifications or recyclable logos on each specific product.
Biodegradable Versus Compostable
People often use the terms ‘biodegradable’ and ‘compostable’ interchangeably – although they’re not the same thing.
Every material will biodegrade if you give it enough time (for example, it takes around 500 years for fossil fuel plastic to break down). That’s why the term biodegradable can’t be verified and is often misunderstood or considered greenwashing.
Compostable, on the other hand, is when a product can be organically recycled in specific conditions. A certified compostable product will rapidly break down in a composting environment – whether that’s a commercial composting facility or your backyard compost. Always look for the certified compostable logo as well as the company’s specific licence number.
Understanding Composting Certifications
Greenwashing is everywhere in the sustainable packaging industry. That’s why it helps if you, the consumer, can clearly recognise certified compostable logos and take a stand against greenwashing.
Any product can claim they’re compostable, but the only source of truth is The Certified Compostable Logo – a registered trademark owned by the Australasian Bioplastic Association (ABA) and European Bioplastics. This logo proves a product is certified home or industrially compostable to Australian and European standards.
Check for these logos along with the company’s specific licence number.
Industrially Compostable
AS4736
Home Compostable
AS5810
Composting In the UK
As an individual, one of the best ways to compost is through your home compost bin.
As a business, you can sign up to Compost Connect, a compost pick-up service powered by Zap Waste, First Mile and X other compost partners. Together, we cover 6,670 postcode districts across London and Birmingham.
Unfortunately, there’s currently no national mandate to implement food and organic waste collection in the UK. By joining Compost Connect, you’ll be leading the sustainability charge and encouraging local governments to get on board.
