How To Make Compost
How to Make Compost
A “How-To” Feature from Lauren Barker, Horticulturalist (May 2008)
You may have tried to make your own compost before with disappointing results, but the truth is you simply need the right combinations of ingredients and once you get the idea it couldn’t be easier. It can be as simple as throwing a few bits in a bin or you can put more effort in; it’s up to you. Furthermore, you don’t need any special tools but a garden fork will come in useful.
A “How-To” Feature from Lauren Barker, Horticulturalist (May 2008)
You may have tried to make your own compost before with disappointing results, but the truth is you simply need the right combinations of ingredients and once you get the idea it couldn’t be easier. It can be as simple as throwing a few bits in a bin or you can put more effort in; it’s up to you. Furthermore, you don’t need any special tools but a garden fork will come in useful.
Why you should compost
- By adding compost to the soil, the nutrient levels will be improved considerably. It will help to improve the soils structure. This means that soil on a hill or a slope will be prevented from moving downwards. It will also help the soil to retain moisture, which is particularly helpful in summer months. Better soil structure will help plant roots to grow and develop. All of these things will help your gardens to flourish.
- Of course the main reason to compost is to reduce waste. Instead of filling up wheelie bins and rubbish bags you can help the environment and yourself.
- Composting has become more and more popular over the years. In the past seven years the number of people composting at home has increased by nine percent. Now, almost a quarter of homes in the UK compost kitchen and garden waste.
- If you buy soil improvers, mulch or compost for your garden you will be saving yourself money, as you will no longer need to buy it when you are making your own.
The Compost Bin
- Every household is different, and people all have different amounts of space for composting. The type of composter you require will be determined by how much space you have.
- If you only have a small space, then a plastic one is probably the best option. They can be fairly compact and have a lid on the top to put your materials in. Some have a door at the bottom where you can remove rotted compost. What’s even better is that plastic composters are often made from recycled plastic. Local councils can also offer recycling bins for free or at a reduced price.
- If you have a large garden you can simply heap up the compost and cover it over with a sheet in a corner which you don't use much.
- It is easy to make your own compost bin, and also rewarding. It can also be made to look quite attractive as well as possibly using up some materials you have lying around.
Making a Wooden Compost Bin· These are the instructions on how to make a square wooden compost box. The size is 1m x 1m x 1m. Interlocking sections are used to build up the composter by stacking them on top of one another. A good material to use is old floorboards or pallets. The following materials are enough to make one section of the box:o 2 x 100cm wooden boards, 10cm wide and at least 1.5cm thick.o 2 x 97cm wooden boards, 10cm wide and at least 1.5cm thick.o 4 x 5cm x 5cm wooden corner blocks 7.5cm longo 20 x 3.6cm screwso 1 screwdriver, 1 drill and 1 saw· One of the 97cm boards needs to be placed on 2 corner blocks. The ends of the board should be flush with the block. The blocks then need to be offset by 2cm. Using a drill create three holes, 3cm deep through the ends of the boards into the corner blocks. Fasten the boards down with three screws. Screw the other end of the board down in the same way.
· Repeat the whole process with the other 97cm board.
· Stand these two boards with the corner blocks attached approximately 1m apart. (You might need a hand with this.)· Place the 100cm board on top of the two vertical boards and make sure the ends of the longer board lie flush with the outer edges of the vertical boards.· Drill two holes at each end of the longer board and screw into corner blocks as for the shorter lengths.
· Turn the section round so that it is stood on the other end. Lay the second 100cm board on top and screw it down as before.
· This is the first section of the compost bin completed. To make the bin 1m x 1m nine more of these sections need to be made. They are then stacked on top of each other as the compost heap builds. Once you have a full bin and you begin using the compost, you can remove the sections from the top and start a new bin. If you made a few extra sections you can have yourself a flexible bin system
Making the Compost- The compost heap must be made from a mixture of nitrogen rich material such as grass clippings and material rich in carbon such as newspaper or bark. You need to have approximately twice as much carbon rich material than nitrogen rich material.
- Grass clippings are rich in nitrogen. They should not be added for a few mowings after herbicides have been added. This is because the chemicals don’t always break down and can remain in the compost making it unsuitable for use on food crops and damaging to plants if it is incorporated into the soil around them. Grass clippings should not be added in large quantities as this restricts the movement of air in the compost which is essential for the rotting process. Care should be taken not to collect cat or dog waste as it can contain the eggs of the Toxocara parasite.
- Take note when removing weeds from the garden as only young, annual (they only live for one year before dying completely) weeds can be used. Perennial weeds and weeds with creeping root systems, such as nettles should be disposed of in other ways as they can survive in the compost. Although annual weeds will rot down quickly they should not be added in large quantities. Just like grass clippings, weeds will become slimy as they rot and will restrict airflow in the compost.
- The following things are rich in nitrogen and should only be added in smaller quantities but nevertheless are essential as they rot down the quickest and get composting started.
- Comfrey leaves
- Young weeds
- Grass clippings
- Chicken manure
- Pigeon manure
- Most kitchen vegetable remains can be included but it is not advisable to include cooked vegetables or meat, as these will attract vermin, especially in areas where they are already rife. The following things can be included in your compost:
- Wood ash
- Cardboard
- Paper towels and bags
- Cardboard tubes
- Egg boxes
- Tea bags
- Coffee grounds
- Old flowers
- Bedding plants
- Old straw and hay
- Vegetable plant remains
- Strawy manures
- Young hedge clippings
- Soft prunings
- Human or animal hair
- Vacuum dust
- Gerbil, hamster and rabbit bedding
- Fruit and vegetable scraps
- Pruning clippings from the garden are ideal for making compost. Do not, however, use clippings that are infested with pests or diseased as these can be passed on when the compost is used. Woody material needs to be shredded to allow it to rot quicker. Here are some other things that take a long time to rot down:
- Autumn leaves
- Tough hedge clippings
- Sawdust
- Wood shavings
- Here is a list of things which cannot be put into the compost heap:
- Meat
- Fish
- Cooked Food
- Newspaper
- Coal and coke ash
- Cat litter
- Dog faeces
- Disposable nappies
- Glossy magazines
- Dairy products
- Plastics
- Metal
- Glass
Additives- Most things that have been put in the compost bin rot down well on their own. Adding nitrogen can speed up the composting process. This can be added as a fertilizer or as manure. Bone meal and dried blood are also high in nitrogen and can be used. Compost accelerators are available from garden centres. A popular one amongst gardeners is Garotta. Most garden centres should stock these things. Manure can simply be added in layers between the other things that have been included.
- To make the best compost in a reasonable time span, air, nitrogen, warmth and moisture are needed. This will ensure the break down of organic matter.
- The most important thing is to ensure there is a good airflow through the heap. This can be done by starting off the compost heap with a layer of thick material such as twigs. This will let the air circulate better. The materials should not be allowed to get too wet or compacted. On the other hand it should not be allowed to dry out either. It should therefore be watered in the summer and a cover put on. This could be carpet or a plastic sheet. Each layer should be different, alternating between fine matter and more thick and chunky matter. The whole heap needs to be turned regularly.
- A small compost heap will not retain enough warmth for the micro-organisms to break down the matter so a minimum size of one cubic metre is recommended. The bigger the heap, the more heat will be created. If a smell of ammonia (like in a baby’s nappy) is being given off there is too much nitrogen in the soil and more material rich in carbon should be added. This could be things like cardboard egg boxes or toilet rolls inners.
Aftercare of your Compost Heap
- After a few days of constructing the compost heap, it should start to heat up. You can feel this by simply putting your hand on the surface of the compost. On cold days you will be able to see steam rising off it. When it begins to cool down, a couple of weeks later it needs to be turned. Remove everything from the container and mix it up. The outside needs to be turned to the inside. If it is too dry water needs to be added. If it too soggy add some dry material. The heap needs to be mixed up to introduce a new supply of air. This will speed up the rotting process. If the heap heats up again, wait for it to cool before turning it again. Continue doing this until it refuses to heat up any more. It then needs to be left undisturbed to finish composting.
- This well constructed heap will soon be home to earthworms and insects, and after six to nine months will be ready to be incorporated into the garden, used for sowing seeds, potting on plants and planting trees and shrubs.
How to know when the compost is ready
- The finished compost will be a dark brown, almost soil like material, very spongy in texture. It will also have a very earthy smell to it. When this stage is reached it should really be left for a month or two to mature. Even if some of the twigs haven’t completely rotted down or some bits of broken egg shell are still remaining, don’t worry. This is still usable and won’t do any harm to the garden at all.
Leaf Compost- Leaves should not be added to your regular compost bin, as they take a lot longer to decompose. They also rot down better at lower temperatures and with less air. They should be piled up in a wire cage and pressed down well with a rake or by standing on them. They need watering in the summer but other than that do not need any more attention.
- It is easy to make your own compost bin, and also rewarding. It can also be made to look quite attractive as well as possibly using up some materials you have lying around.
