Sustainable gardening: How to make your own compost

Sustainable gardening: How to make your own compost

Peter Dowdall has details on a key ingredient for a sustainable garden.

ONE of the secrets of a beautifully lush garden is the soil. The best thing that we can add to our soil is organic matter and this can come in many forms. Perhaps the best type of organic matter that we can add is homemade compost.

In simple terms, compost is a mixture of decayed or decaying organic matter used to fertilise soil. 

We can make our own compost using organic matter such as food and plant material (leaves, grass clippings, and vegetable peels) into some sort of container and letting it decompose as a result of the action of aerobic bacteria, fungi, and other organisms. Organic material is basically anything that is biodegradable.

When composting do include vegetables and fruits, bread, grains, coffee filters and tea bags, eggshells and fruit. Do not compost cooked food, meat or fish, unless you are using a wormery. Do not include cat litter or pet waste because they can contain dangerous pathogens.


If your garden space is big enough then it makes sense to build a large compost bin. Compost bins are relatively easy to build and can be constructed from a wide variety of materials, though my choice is timber. 

Whatever material you decide to use, it is important to protect it from unwanted pests. One way to do this is dig your compost bin into the ground to prevent animals tunnelling under it.

Sustainable gardening: How to make your own compost

The composting process requires air, nitrogen, carbon and water to decompose into nutrient rich soil, therefore, when you are building your own compost bin make sure to consider these elements.

Aerating your composting waste is essential and this can be done using a pitchfork or shovel.

If possible, you should create two or more sections for your compost so that when one section is full it can be ‘left’ to decompose completely while you add more fresh scraps and garden waste to the other section. It can take 12 months for compost to fully decompose and be ready for use on the garden.

The most important thing to remember when making your own compost is to have a good mixture. Don’t just fill your compost bin with grass clippings and expect magic. Grass clippings are a very heavy material and so need to be mixed with a lighter, more open material such as tree prunings or twigs. 

You can also use shredded or ripped paper and the other materials mentioned above, just always remember to keep mixing different materials; ideally, each layer should be about 25cm in depth.

Compost needs to be turned regularly to keep the temperature even: so that some material isn’t always cold, on the outside while the other materials stay warm in the centre of the heap.

Sustainable gardening: How to make your own compost

Finally, you should use a compost accelerator to speed up the whole process. There are many of these available to buy, normally containing enzymes that work on the waste material helping to break it down. 

You can also grow your own. Comfrey is a great plant for this: pulp some leaves in a bucket, fill with water and leave it to stand for a few days (make sure you leave it somewhere where your nose won’t be accosted) then add it to your compost bin and you will be amazed at how quickly it will all start to break down. 

Nettles will work in the same way, just be careful not to include any rogue nettle seeds or roots.

Just in case you were looking for another “lockdown project”, the summer is a good time to get building your compost bin.

For smaller gardens there are other options available such as those below:


A compost tumbler will produce useable compost much more quickly than a regular compost bin because of being turned so regularly. 

If you use it correctly and ensure a good mix of materials you can expect to have usable compost anytime between three and six months.


Another good option for the small or large garden is the green cone. This aptly named green cone is one of the simplest systems for food waste disposal available on the market. 

These sealed cone-shaped devices are buried halfway in the ground and to use them you just dump the food in and close the lid. 

Composting in these green cones does not require any work on your part. All that is required is to leave the compost for six months when you can start taking the finished compost from the bottom.

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