Different Composting Methods

There are many different composting methods, and I thought a reminder might prove helpful. Some types are going to be more relevant for your situation than others, but if you’re not aware what the choices are, how can you make the decision as to what is right for you and your garden?

There are other important matters which you will need to consider: –

how much compost you need to generate
and whether could you generate enough, or nearly enough within your garden
do you want to keep all the composting activity in one, designated area

We’ll come back to these when we’ve looked at the different composting methods, but its good to have them in the back of your mind when reading through the composting options. More in-depth articles on some of these methods can be found in the links below.

Cold Composting

Often considered the “traditional method” its an easy place to start and can be successful. Cold composting uses a compost heap or bin. An enclosed bin works better than an open heap as the organic material heats up more efficiently. It’s also easier to keep the compost at the right degree of wetness/ dryness to break down quickly when it’s contained.

Recycled plastic bins of various shapes and sizes are available. You may find them useful as extra space or for a particular mix where smaller quantities are needed. If your compost bin will be ‘on show’ then consider purchasing or making a decorative one. Wooden bins are also used, often ‘homemade’ using scrap wood to hand and lined with canvas or wool carpet to enclose the compost.

NB compost is removed from the bottom, so ensure there is a easy means of accessing of it.

A minimum of two bins are required, three is better. One bin being filled, one in ‘cooking’ stage, and one ready to use. More is fine as different materials could then be segregated. One of the issues with traditional cold composting is the length of time taken for the organic matter to break down. Little happens over the winter months. Variations on traditional cold bins include Hot bins and Tumbler bins, both speed up the process. These are all more effective if you chop or shred the material before adding it.

Different Composting Methods – Hot Composting

Hot composting also known as hot bin, or hot bin composting is where the compost is contained within insulated closed bins. The heat generated by the decomposing material is retained and so it turns more quickly into useable compost. Because of the heat generated, composting can continue throughout the year.

There are hot bins to purchase, already with insulated sides and lid. Or there is the option of making them on-site, for example using straw or polystyrene packaging for insulation. They are becoming one of the more popular methods of composting with home gardeners.

Then there is the hot composting heap. This is more effort than the above, as, among other things, you have to regularly take the temperature of the compost. It should be at 54 – 60 degrees C for the optimum microbial activity. You also need to keep the mix moist, and aerated, so you’ll need to turn the compost.

For the hot composting heap, you really need to add all of it at once, so that the pile can heat up. You’ll need to get the nitrogen: carbon ratio correct too; this should be 1:25, so its heavy on the brown items.

Tumbler Composting Bins

Tumbler bins, as the name suggests, enable easier compost turning. Looking a bit like oil drums, they may be laid horizontally or vertically within a frame. It’s as simple as turning the handle, although a laden bin may still require some elbow grease! Like hot bins, they generally produce compost quicker than the traditional method. However, they’re not normally hot bins, so the process will still be slower over winter.

Leaf Composting

Leaf composting is generally carried out by the cold composting method, but usually in a mesh sided bin or in leaf compost bags, generally of hessian. The reason for these different composting methods is to allow air to easily circulate around the decomposing leaves. Certain tree species take longer to compost down than others. The end result is a very useful compost, especially if you need ericaceous soil for your potted Camellias! A read through of the making leaf compost blog may be helpful.

Different Composting Methods – Wormeries

Wormeries utilise worms’ gourmet tendencies and are suitable where less waste is generated or as an extra bin. Children often like to ‘feed the worms’ which makes it ideal if school holiday activities form part of your work schedule. Brandling worms are the most usual species in a wormery. They’re native to the UK, but less of a burrowing worm, so better for this situation.

Various types can be bought, and yet again they can easily be ‘home-made’. One of the benefits of a wormery is that it produces a nutritious liquid which can be diluted and used as a liquid feed. This is in addition to the compost itself. Worms do need some shelter from the worst of the wet and frosty weather so site your wormery with this in mind.

Bokashi Composting

Bokashi was originally a Japanese system of composting. The above methods use oxygen as part of the composting process, whilst bokashi excludes it. Bokashi compost will not smell as ‘rich’ as other compost because it is an anaerobic method of composting, but it should not smell sickly.

This method can compost bones and cooked food, but doesn’t rot down as fully as the methods above. The fermented ‘mush is added to an ‘ordinary’ compost bin or dug into the soil. It also produces a rich liquid which can be diluted and used as a plant food.

Sheet Composting

Sheet composting is also known as lasagne gardening, lasagna gardening, sheet gardening, layer gardening, no-dig gardening and no-till gardening. It is a method of composting or mulching where plants are grown directly into the mix. Hence it is also a method of cultivation that doesn’t require digging. The layers of cardboard, leaves, green plant waste, straw and so on form a nutrient rich bed. You can then grow your vegetables, fruit and flowers on this easy to work soil. An organic mulch is laid at the end of the growing season as you would in a traditional bed.

Trench Composting

I always think of trench composting as being a compost bin below ground; it is one of the traditional methods of composting. It’s an excellent method for composting as many vegetables respond well and it reduces the on going labour and feeding requirements. For example, fast growing peas and beans, pumpkins and courgettes love it. As do brassicas such as cabbage and Brussels sprouts that stand in the ground for some time.

As a method of composting it is best carried out in the autumn and left over winter to then be planted on in the spring. This gives time for decomposition to occur. Some garden situations are less suitable for this method, such as very wet ground over winter.

Hot Beds

Would you believe that there are still more options for different composting methods? For example, hot beds, which are a method of cultivation based on hot composting. These tend to be used for growing slightly tender plants such as pineapples and melons, and may be below ground or in a special compost bin with a removable glazed top.

Different Composting Methods – other considerations

A recap of those questions –

how much compost you need to generate?
could you generate enough, or nearly enough within your garden?
do you want to keep all the composting activity in one, designated area?

If we consider the middle of those items first, its fair to say that not many gardens can generate all the compost they need. But recycling your garden and kitchen waste on site is beneficial in so many ways, that even small amounts are worth making.

Back to that first question – this is obviously going to depend on your particular garden, but will be affected by –

your soil type and how nutritious it already is
what you intend to grow in your garden, eg shrubs, annual vegetables, fruit trees, wild flower meadow
how big the garden is
whether you be using the homemade compost as part of a mix for pots and for seed sowing

But as an example for roughly estimating, try this comparison. Using the compost as a mulch, if it was in one of those 40 litre bags of peat free potting compost, it would cover an area of soil roughly twice the area of the bag’s top surface at half the depth of the filled bag.

Different Composting Methods – all in one place?

And so to the last of those questions – do you want to keep all the composting activity in one specific area?

This is often a good idea and I do regularly design in a utility area with compost bins, water butts, storage for pots, wheelbarrow and so on. But it won’t suit every garden – or indeed every type of composting. For example, if you ‘re using trench composting, that doesn’t need a bin. An ‘in use’ bokashi will be in or near the kitchen.

However, depending on the size of your garden, it may be more efficient to have two composting areas, so that you’re not carting compost long distances. In a smaller garden, a decorative compost bin and a wormery near to the raised vegetable beds might be the best option.

The critical thing is to know how your garden works as a whole, because then its easier to consider how to make it both practical and pretty. We have an easily downloadable ebook “Compost and Composting” which includes helpful tips and much more. Whether you’d like it for yourself or as a present for a gardening friend it is easy to take into the garden on your mobile!

If you would like help with learning more about your garden and gardening, why not ask about our bespoke Gardening Lessons, where your classroom is actually your own garden. We can help you learn gardening basics, carry out worm and other experiments and also show you how to plan an ornamental border or kitchen garden.

And for further gardening advice and inspiration, check out Plews Potting Shed blogs, including the selection below and our monthly Tipsheet – You could come and find us on Instagram Pinterest and Facebook too.