Welcome to our series of posts on the A-Z of zero waste!
An overview of everything that has been shared so far can be found here.
Today we're talking about composting! This may not seem initially like a key part of zero waste living but hopefully by the end of this article I can change your mind and convince you that trying to compost is crucial no matter where you are.
So it is important to preface this article by saying that composting is not our first point of call for organic matter as firstly we want to get as much use out of it as possible. That means using food scraps in other ways, like in smoothies or making stock with veggie scraps, and recycling paper and cardboard so it can be reused first before being rotted down. We will be tackling food waste later as it's such a huge topic that it deserves its own post. But eventually you get to a point where food cannot be used any more, and paper can no longer be recycled. What then? Well then there is compost.
Composting takes organic matter (food waste, garden waste, paper and cardboard) and rots it down into compost. It copies the natural process where organic material from leaves and rotting fruit falls onto the ground and rot down to become fertiliser for the trees themselves, so that nothing is wasted. Composting is brilliant for a few reasons.
1. Composting saves resources
- Food scraps still have essential nutrients in them that can benefit plant life and if we send them to landfill then we are just wasting the nutrients and minerals that are in them.
- When compost is applied to soil it increases how much water it can retain, so plants and crops don't need to be watered as often as that water is stored within the soil.
- Compost reduces the need for artificial fertilisers to be used as it provides a natural source of nutrients for the plants, and it avoids the resources needed to create these fertilisers.
- Using compost to keep organic matter out of landfill extends the use of our landfills. Landfills are often toxic and polluting so reducing the number of them we need is essential.
- By avoiding sending organic matter to landfill we reduce the volume of rubbish going to landfill and so also the number of rubbish collection vehicles on the road needed to collect it all. This reduces air pollution and traffic around residential areas.
2. Composting reduces green house gas emissions
- You would be forgiven for thinking that food waste breaks down in landfill like it would on a compost heap, after all it is biodegradable, but unfortunately you would be wrong. Due to the lack of oxygen in landfill, organic matter can fossilise, or even break down into methane, which is a more potent green house gas than carbon dioxide.
- In some places the rubbish is burnt so the nutrients in the organic matter are completely wasted and just converted into more green house gases.
- Again because we are reducing the volume of rubbish we are also reducing the emissions from vehicles that collect and transport our rubbish.
3. Compost improves our soil quality
- We have everything we need to survive on earth but it is held in balance. If we are continually taking nutrients from nature in the form of our food and not replacing them because the organic material is ending up in landfill then our soil quality is going to progressively get worse until the point where is can no longer sustain growth. Whilst it slowly loses quality, it retains less nutrients meaning crops grow less and are poorer quality. More compost means improved yields and plant nutrient quality.
- Compost improves water retention in the soil making crops more resistant to drought.
- Unlike artificial fertilisers, compost is a natural fertiliser that is slowly released into the crops. It's also less likely to be washed away into waterways, which risks eutrophication and can damage life in water ecosystems.
- Compost improves the texture of soil leading to better air circulation around plants.
- Compost also helps reduce soil erosion.
4. It can save you money
- If you compost, it may also save you money as you might not need to buy bags of compost or artificial fertilisers.
- It will also save you money if you pay to have your rubbish collected, as you will be sending less to landfill.
If we compost organic matter, it produces less methane than in landfill (if aerated properly), returns nutrients to the soil and in doing so increases the quality of the soil meaning more capacity to hold water and more nutrients that go back into the plants we eat. The more compost we make and put back onto soil, the more plant growth can occur, taking CO2 out of the atmosphere by photosynthesis and drawing it down into the soil as a way to reduce green house gases in the atmosphere.
Compost is not only sustainable, it is regenerative and has the capacity to help tackle the climate crisis we are currently facing.
Each person in the UK generates around 170kg of organic waste each year. If a quarter of us switched from dumping organic waste in landfill sites to composting it, we'd save the equivalent of 2.5m tonnes of CO2 from reaching the atmosphere each year(1). That is the equivalent of the electricity use of 435,966 homes for one year. (2)
Okay you have convinced me, composting is awesome, but how do I compost?
There are so many different ways you can deal with organic matter and the best one will differ based on your circumstances and your location.
If you have access to kerbside food collection or garden waste collection that can be a great way to deal with organic food material. You can also try any of the other methods below to generate your own compost for your garden and plants.
If you don't have kerbside collection, but have a garden the simplest might be a garden compost pile or compost bin. These come in many different forms, from an actual pile at the bottom of your garden, to compost bins, compost boxes and compost tumblers. They also vary in size so you can get one that suits your waste and how much compost you can use. Some councils even subsidise the cost of buying a bin to encourage you to start composting.
If you don't have access to outside space you can consider either a worm bin (wormeries) or a Bokashi compost bin.
Worm bins are a great way of dealing with food waste by using worms to break down organic matter into into worm cast compost (vermicompost) and a liquid plant feed (leachate), which you can use in your garden and around your home. Find out more about wormeries here.
If that doesn't appeal to you, what about a Bokashi bin? Bokashi composting is a no-smell, process of fermentation using Bokashi bran and microorganisms to break down organic matter, producing compost and liquid plant food. Find out more here.
If none of these work for you, look out for local places near you that accept composting. Check out online what is on offer near you. Does a neighbour compost and would be happy for you to add your food waste? Are there local allotments which would love your organic matter to turn into compost? Places like Nextdoor, facebook market place or free cycle may be places to check out to see what is available near you.
Resources for dealing with food waste, garden waste and compost in the UK:
Kiss the Ground - Inspiring participation in global regeneration, starting with soil. Check out two of their videos below.