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Composting Waste

Last updated on 24th April 2023

According to the Office for National Statistics, in 2020, the total weight of waste from households in England reached 22.6 million tonnes. This is a slight increase from 22.1 million tonnes in 2019.

Other organics in waste from homes (including green garden waste, mixed garden and food waste, wood for composting and other compostable waste) made a significant contribution to the overall recycling rate, making up 15.8% of all waste from households. However, these figures were down somewhat compared with 2019, largely due to the reduced collections of waste as a result of the Covid-19 pandemic.

What is composting?

Composting is an environmentally friendly way of handling garden and kitchen waste. In fact, it is the best possible thing to do with such waste! Not only does composting dispose of unwanted waste, but it also produces compost that can be put to good use in the garden as an excellent way to improve the soil.

Composting is nothing new. It is nature’s own recycling bin, turning organic waste into fertiliser. More and more of us are turning to alternative means of dealing with our waste, and compost heaps and bins have been increasing in popularity in recent years.

Man in garden

What are the different types of composting?

There are a few different methods used in composting. Some types are more useful than others depending on a person’s (or a garden’s) need. There are other factors to consider too, such as the amount of compost you need to produce and the amount of space you have. Let us take a look at some of the methods.

Cold Composting

This is often the one that most people think of when they think of composting. It is a fairly easy method to get started. Many people use an enclosed bin rather than an open compost heap as the material in the bin heats better and it is much easier to keep the compost at the right moisture levels.

As compost is removed from the bottom of a heap or bin, you need to think about how you will remove it. A potential problem with this method is that it takes a while for the material to break down.

Hot Composting

Hot composting can also be called a hot bin. This is where the bin is closed and insulated. The decomposing material generates heat which is kept in by the bin’s insulation and therefore it makes compost at a quicker rate. The ideal temperature for a hot composting bin or heap is between 54°C and 60°C.

This is because the microbial activity is at a peak between these temperatures. You can achieve hot composting in a heap too, but it is a little more difficult. The compost will need to be kept moist and aerated, so will need to be turned over.

Tumbler Composting

Tumbler bins, as the name suggests, tumble! This makes it easy to turn the compost. They tend to produce compost quicker than a heap or traditional bin.

Leaf Composting

Leaf composting is usually a cold composting method in a bin with mesh sides or in special hessian leaf compost bags. This allows air to circulate around the leaves. Some tree species take longer than others to decompose. The compost at the end is great if you need ericaceous soil for certain plants such as Camellias.

Worm Composting

Worm composting (also known as vermicomposting!) uses a wormery. Wormeries are quite small and are ideal in homes where there is not much waste generated. They are often great for children as they love going out to feed the worms. The best species of worms for wormeries are brandling worms, which are native to the UK. They make a great species for wormeries as they do not burrow as much as other worms.

A benefit of worm composting is that it produces nutritious liquid which you can dilute to make a liquid feed. What is more, you will still have the compost produced too. Wormeries need to be sheltered, so this is something to bear in mind if you are thinking of taking on worm composting.

Bokashi Composting

Bokashi, as you may have guessed, originates from Japan. Bokashi is different from the other methods of compositing mentioned so far because it excludes oxygen from the process. If you go back to your GCSE Biology course, you may remember the terms aerobic and anaerobic – Bokashi compost is anaerobic, meaning without oxygen.

Compost from the Bokashi method will not smell quite as ‘rich’ smelling as other compost but, equally, it should not smell unpleasant either. With this method, you can compost cooked food and bones too, but there is not as much rotting down as the aerobic methods. The mush becomes fermented and can then be added to a standard compost heap or bin or placed in the soil. This method also produces a liquid that you can dilute and use as food for plants.

Sheet Composting

Sheet composting is quite an easy method if you have the space. People call it ‘lasagne gardening’ because of its appearance. This method of mulching or composting is where you grow plants directly into your mulch. It does not require digging, which is a bonus for those who dislike it! There are layers of cardboard, green plant waste, leaves and straw which form a bed where you can grow fruit, vegetables and flowers directly.

Trench Composting

Trench composting is as it sounds! It is rather like a compost bin that is below the ground and is a fairly traditional composting method. Vegetables respond well to this type of composting such as pumpkins, courgettes, cabbages and fast-growing beans and peas! You should begin the process in autumn, leaving the material alone until you are ready to plant on it in the spring. If your garden is very wet in the winter months, this method would not be an ideal choice, however.

Recycling organic compounds from food waste with composting

What are the benefits of composting waste?

Composting is essentially recycling the organic compounds in food waste and vegetation. It has demonstrated that it significantly reduces the amount of food that is thrown away and is an important option for dealing with organic waste. This reduces the amount of waste going into landfill. As a result, it is a sector that is rapidly gaining in popularity, turning our rubbish into a valuable commodity.

What is more, composting waste helps to replenish essential nutrients and elements in our ecosystem. Given that it is human actions that are mostly responsible for the depletion of such elements, doing a little bit to restore them through composting is of great benefit.

Composting can be done easily at home. Organisations such as the Royal Horticultural Society recommend home composting instead of using council green waste collections. This is because composting at home is even better for the environment due to not needing heavy transport and its associated costs for the environment.

Another advantage of composting is that it is flexible and can be done all year.  As soon as you generate suitable materials from the garden or within the home, they can be thrown on the compost heap. This benefits your home and your garden!

How to start composting?

Composting is not restricted to garden size. It is useful in any garden, no matter its size. If you have a tiny garden, it may be difficult to find enough space and enough material to put in your compost heap. However, there are ways that you can still benefit from composting such as by considering worm composting!

If you are looking to start composting your household organic waste and garden waste, it is important to choose an appropriate place within your garden to do so.

The place you choose should be stable in terms of temperature and not exposed to any extremes when it comes to moisture either. The compost heap works thanks to microorganisms that convert the waste into compost. These bacteria and fungi work optimally if their conditions are kept constant. As such, a compost bin would work best in a shady area.

Compost bins or heaps work best when they have an earth base rather than a solid, paved or concrete base. This is because an earth base allows for drainage and also means the organisms in the soil can work their magic in the compost heap.

If your only option is a solid base, add some soil onto the bottom of the compost bin before you start to throw in your waste. You could even start simply by digging a hole in the earth and filling it with your compostable waste then covering it back over with soil!

A compost bin retains moisture and some warmth which makes compost much more quickly. However, open compost heaps still compost eventually if you are patient! Any specialised container will produce compost if it is protected from rainfall, has suitable drainage and lets in some air. Larger bins are much more effective than small bins.

How to compost food waste?

Despite the famines and food shortages in the world, food waste is actually a big problem. According to the charity Waste and Resources Action Programme (WRAP), the UK throws away 9.52 million tonnes of food per year, emitting 25 million tonnes of CO2. This staggering figure is more than the annual total emissions from countries like Kenya. In fact, the average rubbish bin comprises of around 30% food waste.

The most wasted food according to WRAP is potatoes, with over 1.6 billion of them being thrown away every year. Fresh vegetables and salads total 28% of all thrown away edible food waste. Other foods are thrown away because they have not been used before the end of their shelf life.

With all this food waste often going to landfill, it is no wonder that people are looking for alternatives for food waste such as composting. Even if you were extremely careful with food, you would still produce some food waste such as eggshells, banana skins, orange peel and bones.

Your compost bin or heap should comprise of around two-thirds wet food (or garden) waste. When you peel potatoes or have lettuces past their best, you simply throw them onto your compost heap or in your compost bin and the compost will work its magic over time. It is important to get the balance right with other matter such as garden waste and dry materials, however.

How to compost garden waste?

The vast majority of garden waste is suitable to be placed in a compost bin or heap. This includes leaves, small branches, grass cuttings and garden clippings.

These can be added to a compost bin as and when they are produced. Of course, there will be times of year when you produce a lot more garden waste than others such as the summer months with grass cuttings and the autumn with vegetable patches and autumn leaves. As mentioned above, it is important to have the balance right of wet and dry components.

What food waste is compostable?

To avoid attracting vermin, you should only use uncooked food in your compost bin or heap. Aside from that, almost anything goes. Getting the balance of a compost bin right is key, and food waste provides nitrogen-rich materials that are needed to produce compost. Add your potato peelings, apple cores, coconut husks, orange peel, cauliflower leaves and pumpkin flesh from Hallowe’en. You can also add coffee grounds and plastic-free tea bags too!

Vegetable waste

What garden waste is compostable?

Garden waste provides many of the carbon-rich materials needed for composting. Most garden waste is suitable for composting including branches, twigs, dead flower heads, grass cuttings, fallen leaves, fruit dropped from trees, clippings from pruning and animal dung such as manure or chicken droppings.

Seaweed also makes a good addition if you live near the beach. You can also add weeds from the garden, but it is wise to only add weeds that have not set seed and ones that do not regrow from their roots, for obvious reasons! Straw such as that used in animal bedding can also be added as can wood chips and sawdust.

What other waste is compostable?

Aside from food waste and garden waste, untreated paper, cardboard and cotton can also be added to the compost heap. These provide additional carbon-rich material needed for composting. There are also compostable ‘plastic’ bags and some biodegradable food packaging now too which you can add to your compost without worry.

What is non-compostable?

Many things are not suitable to be thrown on the compost heap. Of course, this includes plastics and anything non-biodegradable. However, you also should not add things such as waste from the vacuum cleaner or lint from the tumble dryer. These usually contain microplastics and synthetic materials which will not decompose.

When is the compost ready?

Compost usually takes around one month to a year to become ‘mature’ depending on the intended use. If you plan to use compost as a dressing to soil, it won’t take too long. Finished compost in which to grow plants, also called humus, will take the most time and it is important to get it right as unfinished compost could damage plants.

Finished compost will be dark in colour and have an earthy smell. It will be crumbly in texture. When looking at the pile, the volume of it will have reduced by around half and no visible organic items will be remaining.

You could test your compost by doing a germination test such as using radish seeds. Radish seeds germinate quickly. If you put some of the compost into containers and sprinkle it with the seeds, compost that is ready will mean that around 75% of the seeds will germinate and then grow into radishes.

How do you maintain compost?

It is important to get the balance right when it comes to composting. This balance needs to be between materials rich in nitrogen and those composed of carbon compounds. The perfect ratio will depend on the composting method too.

Compost scientists claim that the quickest way of producing fertile compost is to keep a ratio of around 25 parts carbon material to 1 part nitrogen material. If the carbon is too high, it will slow down the process. If the nitrogen is too high, the pile will end up significantly smelly.

The RHS suggests aiming for 25–50% soft green materials such as your grass clippings and vegetable food waste which will feed the microorganisms. The rest should be woody brown materials such as wood chippings, dead leaves, paper, cardboard and straw.

Aside from maintaining the compost itself, you will also need to ensure that the site is maintained. Using bricks or netting to surround your compost heap will reduce the likelihood of vermin getting in. Of course, hedgehogs and other small animals may be attracted to the compost due to its shelter and warmth, so bear this in mind when maintaining your compost.

Compost should be turned over as this adds air which the heap needs to be able to decompose (unless you are excluding air like in the Bokashi composting method!). If the heap becomes compacted or wet, the compost will take longer to be ready as there is not as much air available.

You should place quite a lot of material in the compost bin or heap at once and then turn it every so often (perhaps once a month) to get the air in. The main reason that compost heaps or bins give poor results is due to the failure to turn over the materials.

For most of us, we add to our compost bins slowly rather than in one go. Unfortunately, this does mean that home compost is not often as good as compost made professionally in huge quantities. However, it can still be effective.

Compost bin

What problems can you encounter with composting?

Of course, as with anything you try yourself at home, you may find that your compost results are not quite right. Let us take a look at some common composting problems.

  • Why is my compost strong-smelling, slimy and wet?
    For this problem, it is usually a case of too much rainwater and not enough airflow. Make sure your heap is protected from rainfall and add in some more brown, woody materials such as shredded paper, woodchip or straw.
  • Why is my compost fibrous and dry with not much rotting?
    This problem means there is possibly too much brown material such as wood and not enough moisture. To overcome this problem, you can add more green materials such as grass or vegetable peelings. Some use a bucket of manure to help or add a commercial compost accelerator like Garotta.
  • Why is my compost heap troubled by flies?
    If your compost bin or heap is well-maintained, there should not be too many flies flying about. However, if they become a problem, make sure that you put a layer of garden waste on top of any kitchen waste in your heap or bin. Make sure that the pile is not too wet either and give it a turn if it needs one.

The Takeaway

Many of us could benefit from the use of a compost heap or bin in our gardens, regardless of how much waste we produce. What is more, composting waste does not only help us get rid of our waste but also helps the wider environment too.

About the author

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Laura Allan

Laura is a former Modern Foreign Languages teacher who now works as a writer and translator. She is also acting Chair of Governors at her children’s primary school. Outside of work, Laura enjoys running and performing in amateur productions.

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