Making your own compost from the ‘brown’ and ‘green’ waste generated from your garden and kitchen produces a valuable garden resource that can be used to improve soil structure; breaking up heavy clay soils to make them more workable and improving the moisture retaining properties of lighter, free draining soil. The decomposed organic matter is very dark, almost black in colour as it contains a lot of humus, a beneficial soil-improving material your plants need, humus is also, a natural source of ‘slow release’ fertiliser for plants and holds onto nutrients that would otherwise be washed away by rain and watering. So, stop putting out your ‘Black Gold’ ingredients for the local authority to collect, make your own and reap the rewards of high quality compost and save money too!
The bin …
The easiest and possibly quickest option is to buy a plastic compost bin; they are long lasting and lightweight, the plastic lid will retain heat and prevent the decomposing materials from drying out. If you’ve got the time and the DIY skills of ‘Tommy Walsh’, you can create a home-made compost bin out of pallets or reclaimed wood; for a lid, use a piece of old carpet or tarpauling. Once you’ve decided on the approach to take, choose a site that gets some sun for part of the day; a level, well drained spot will ensure that excess water can drain away and allow nature’s perfect waste disposal unit, worms, to get in and get on with the task of breaking down the contents.
So What’s in the mix?
Compost heaps need a mix of brown and green waste to encourage the pile to heat up and decompose efficiently.
The ‘brown stuff’ is woody or carbon rich waste i.e. woody plant prunings, egg boxes, scrunched up paper, cardboard, small amounts of fallen leaves, hay, straw and wood chippings or sawdust. These are slower to decompose but provide vital fibre and carbon and allow air pockets to form in the heap to keep your compost healthy.
The ‘green stuff’ is leafy or nitrogen rich waste i.e. leafy plant matter, tea bags, small amounts of grass clippings and fruit / vegetable kitchen waste. These are fast to break down, provide nitrogen and moisture to the heap.
The ‘magic ratio’ of materials, to produce a fast decomposition of materials is, 25 parts carbon to 1 part nitrogen. Vary the size of the materials added too; the smaller the particles added, the quicker they decompose.
Weeds that have gone to seed or that spread by their roots, diseased or insect infested plant materials, grass clippings or weeds that have been treated using chemicals. The heat, which can be generated by a compost heap, can kill off many diseases and insects but this is not a guarantee; spreading compost over your garden containing weeds, seeds and disease will inevitably have a negative impact on your garden.
Kitchen scraps i.e. meats, oils, fish, dairy products and bones, the final NO is cat litter, pet poo – dog, cat, pig or human from a baby’s nappy. You are certain to attract rats, unwanted pests and create a foul smell, with this lot in your heap!
Didn’t achieve the magic mix?
If you didn’t manage to get the right balance of green to brown waste your compost will be too wet or too dry respectively. Too wet; adjust the mix by adding some more brown material and conversely too dry, add some more green.
Hot, happy and healthy….
Build a pile with a balanced carbon / nitrogen ratio and the heat will build up quickly; if you carelessly throw anything and everything onto the pile, it won’t assist the heating process and you’re left with a cold, unhealthy pile that could take years to decompose.
To maintain a healthy heap….
Keep it moist – dig down into the pile to check the water content, it should be moist and not soaking wet. If it’s dry add water but be mindful that water removes air spaces in the heap and can lead to an unhealthy heap. If it’s soggy, the mix has too much green waste, add some brown.
– aerating the compost heap is essential to provide the conditions required for aerobic bacteria to break down organic matter. Aerating tools are used with a twist / turn action in the heap to lift and mix compacted layers. Alternatively, the most effective method of adding air to a heap is by turning it. Ready for a work out? Take a garden fork; remove the outside layers of the heap and put them aside; remove the inside layers into another pile. To re-construct the heap, place the outside layers in the centre and the inside layers around the outside.
– ‘More is best’ when it comes to turning heaps. Turning promotes aeration, mixes the heap thoroughly and speeds up the decomposition process. This in turn, reduces the time is takes to make your compost to as little as two to three months in the summer. The end product should be a soil-like substance, dark brown almost black in colour and crumbly with an earthy smell.
Go ahead and spread –
Use your finished compost as a soil conditioner; it will release nutrients as it breaks down over one to two years; lightly fork at least 5cm of compost into the soil surface.
Or, if you need a rest from turning, add your compost as a 10 cm thick surface mulch and let earthworms do the mixing for you. Apply it in spring to provide nutrient as well as conserving moisture in the soil. With this in mind, leave a gap around the bottom of plants and shrubs to avoid rotting the base.
Use it as a basis for potting compost; sift the compost and mix in equal parts with top-soil and horticultural grit.