Home made garden and kitchen compost is an excellent and affordable way of adding nutrients to your garden soil and improving its structure. As seasons pass, the plants we grow in our gardens continually take up nutrients leaving soil depleted of goodness. Home made compost is a simple way of putting back what our plants have taken out and the great thing is that it is mostly made from the parts of those harvested plants that we have not eaten. Recycling is a huge part of sustainable and resourceful gardening and a compost heap allows us to productively dispose of unwanted plant matter so that we can reuse it as compost.
Good compost willnot only promote strong growth in plants, it returns organic matter to the soil to feed micro organisms and earthworms that help to maintain a healthy and productive soil. Compost enriches soil and assists in drainage as well as moisture retention.
Use compost for enriching and conditioning soil before planting new crops in your beds and planting areas. Compost is particularly useful in spring and summer when hungry plants are drawing on nutrients and moisture in your soil. It is a good general purpose fertilliser and can be used all year round.
Compost, like well-rotted animal manure, can be dug deeply into soil to help improve its structure and to store nutrients for deep rooted vegetables like parsnip, artichoke, carrot, beetroot and turnip.
It can also be turned into the top few inches of garden soil to be more readily available to fast growers such as lettuce, spinach, peas and beans. The quantity you should use can vary, but one or two spades full per square metre ( a stride by a stride) is generally recommended.
Applying compost in your garden: Spread compost onto your beds with a spade or shovel and then dig in using a fork – this saves chopping up too many of the worms that you’ll almost certainly find living in it.
Scatter compost across beds and turn into soil with a spade so that fragments of manure and soil are visibly mixed to about a fork’s depth for general soil preparation and conditioning.
Compost can be added to individual planting holes (maybe a handful or two in most cases) when planting the likes of rhubarb, globe artichoke, zucchini, melon, tomato and other hungry high producers – just mix in with soil at the bottom of the planting hole before you put your plant in.
For hot and fast compost gather up all the ingredients you will need to fill a bin, or two (there are always plenty for sale on Trade Me)
Remember you'll need about 3 times more 'brown' /high carbon ingredients to 'green'/high nitrogen.
I beg, steal or forage for whatever's going : straw, saw dust, leaves, windfall fruit, manure, grass clippings. Food scraps are good too of course, but ask family and friends to collect them up for you for a week so you end up with a decent amount. Make friends with farmers, hay and sheep poo from the hay barn floor is brilliant!
Place your bin directly on soil.
Layer the ingredients up in your bin - 2 or three inches of each ingredient and a decent sprinkle of water on each layer.
Turn the compost at least once a week by just emptying out the contents and piling them back in again. More fun than the gym!
This is a good opportunity to add more browns or greens if you think your ratio is not quite right, or just to bulk it up a bit more and of course add plenty more water to each layer as you refill your bin.
You'll have delicious, worm filled compost in 6 to 8 weeks.
There are a wide variety of pre-fabricated compost bins, tumblers and kit sets for sale but you can fairly easily make your own from recycled timber, macrocarpa boards, sheets of roofing iron or simply chicken wire stretched between steel waratahs. It is best to build or place your compost bin on bare soil to ensure instant contact with micro-organisms and earthworms in the soil that will help to decompose waste material. Ideally you should have 2 or even 3 compost bins so that one is being filled whilst the other is full and ready to use. Heat is an important part of speeding the composting process so position your bins in a sunny spot. A compost bin may get a bit smelly – especially during summer – so place away from areas where a pong could be a problem.
NB. Rats are often attracted to compost bins and heaps both as a food source and as a warm place to build a nest. Only composting vegetable matter is a good way of reducing the attraction to unwelcome pests.
So that you can easily get access to your compost and turn it, its best if your bin is about a stride wide by a stride deep and no taller than about waist height.
Ingredients - Kitchen Compost
Keep a small bucket or bin in your kitchen and fill it with any of the following:
Fruit and vegetable scraps (only add unwaxed citrus – and in moderation)
Coffee grounds and tea bags
Egg shells (scrunched up they are good for drainage)
Paper, toilet roll centers and cardboard without coloured ink (remove any sticky labels and tear into thin strips and scrunch up before adding)
Egg cartons - with glossy labels removed (tear into small pieces before adding)
When the bucket or bin is full simply add to compost bin in the garden.
Not to be composted: Meat, fish, cheese which will attract rats (These can be composted in Bokashi composters or fed to chickens if you have them)
Ingredients - Garden Compost
Lawn clippings – added in thin layers between straw and garden waste to stop a thick layer building up and going slimy.
Annual weeds such as chickweed, cleavers and bittercress (pick before they set seed)
Thinnings from rows of sown plants, dead leaves and any waste material straight from your vegetable beds (thick stems and items larger than an egg should be chopped into smaller pieces before adding).
Not to be composted: Bulb forming weeds like oxalis and onion weed (foliage is okay but anything beneath the soil is a ‘no no’) and perennial weeds such as bindweed, kikuyu grass and couch grass (roots in particular) – roots and bulbs may survive the heat of the compost heap and then regenerate in your garden. Woody prunings and cuttings and evergreen foliage that is slow to decompose (leaf matter can be composted separately in a heap and makes a great soil conditioner rich in organic material)
Dog or cat poo which can contain parasitic worms.
Seaweed can be added straight to the bin every now and then to increase decomposition.
Chicken, sheep, cow or horse manure can be added to help feed the composting micro organisms and speed their work.
A sprinkling of garden lime every time you empty your kitchen bin or bucket or add a load of trimmings form the garden will help speed things up.
Add your own pee to your compost every now and again, the nitrogen helps to break down organic material and raises the temperature of the heap which helps to kill pathogens and weed seeds. Don’t drench your compost in pee as it contains salts that can harm micro organisms and worms if concentrated.
Bokashi composting is a great way of recycling kitchen waste such as vegetable trimmings, meat and fish in a sealed container that produces a rich liquid compost as well as composted material that can be dug into the soil. Bokashi composters can be kept in the kitchen close to the sink and chopping board and their sealed lid makes them pretty much odour-free. Bokashi composting uses EM ‘Effective microorganisms’ that can break down meat and fish which that otherwise are not normally added to garden compost bins or wormeries.
Building your compost
The aim is to build your compost from a mixture of ‘green’ vegetative matter and ‘brown’ material such as straw, paper and cardboard. Ideally you will mix paper, straw, cardboard, kitchen trimmings and garden waste 50/50 as you fill the bin. If, however you add a single layer of ‘green’ then follow this with a layer of ‘brown’ for balanced decomposition. All material should be added as small pieces, this means chopping up fibrous cabbage bases, broccoli stems, old carrots, strands of seaweed and the like and tearing up paper or cardboard and scrunching it up. If you are adding material in fairly regular layers then you might want to turn the compost in your bin with a garden fork every couple of weeks to ensure that air gets into it and ‘green’ and ‘brown’ particles are well mixed. Covering the compost in the bin with a piece of old carpet or a few sacks helps keep things warm which ideal for good decomposition. Generally the right balance of ‘green’ and ‘brown’ waste has sufficient moisture but it can be worth damping down any layers or large quantities of ‘brown’ waste with a watering can when they have been added to the heap.