Making your own compost is one of the easiest, most fun and beneficial things you can do for your garden! Gavin Heron from Earth Probiotic guides us through the process of making compost and why it’s so beneficial…
Compost is a natural process where micro and macro organisms break down organic matter thereby making this food source available to plants. Nature does this all the time; what do you think happens to the leaves in a forest after autumn? They go back to the soil and feed the tree in the Spring (basically a natural food larder)
First, Why Make compost?
When you dump your garden and food waste you are throwing away nutrients.
Your plants pulled nutrients from the soil in order to grow. So when you dump them you are, over time, reducing the health of your soil and thus your garden. And it is also silly to throw away your garden nutrients and then buy it back from someone (or worse add synthetic short-term fertiliser).
Additionally, when your garden waste is dumped into a landfill it rots and emits dangerous Greenhouse gases while leaching pathogens into our water system. Not good!
So here are some tips on making great non-smelly, crumbly and full of all the good stuff compost…
Trust me, once you start you’ll become that weird compost person who is more proud of the dark crumbly stuff than of her glorious tomatoes.
Plus we have some useful products available in-store like composters, digesters and food waste recycling bran to help you get your compost going…
How to Make Compost
Compost requires a balance between carbon and nitrogen rich material. Carbon rich woody stuff (or browns). Nitrogen is leafy stuff (or green). Ideally you should have 2 to 3 times more brown stuff than green stuff.
If you have too much brown your compost will be very slow and you won’t get much heat. If you have too much green then you’ll have a smelly slimy heap.
(Either way, both will eventually turn back to soil).
The challenge is that in Summer we have huge amounts of green grass. And in Winter an oversupply of brown leaves and twigs from our Autumn pruning. We find dealing with an over abundance of brown material easier than dealing with too much green. That’s because we’re not in a rush and would rather avoid the ammonia smells from having too much nitrogen. Also, the brown stuff is easy to store until it is needed (or even, in Autumn, make leaf mould).
But there is a trick to Summer composting. You can easily use cardboard as a brown for your compost. So serviettes, newspaper (not the shiny stuff), paper rolls, cardboard boxes (we always ask the grocer to add our veggies into a cardboard box for precisely this reason). Just tear up these inputs into small pieces and add them into your compost with your lawn clippings.
TIP: The smaller the pieces in your compost the faster they’ll break down – if you have the cash, get a chipper/shredder.
Ok. So how do you start composting?
- Identify a space in your garden for your compost heap. Semi-shade is best. Full sun is better than total shade.
- If you’re going to add kitchen scraps to your heap, then locate it close to your kitchen. You don’t want to, gradually, neglect it because it is inconvenient. In the end we, like water, find the easiest path to get things done (or not done).
- Decide on your ‘method’. Are you going to add it to a closed compost bin, just leave it in a pile, buy a tumbler, invest in a composting bag, or have a three bin system using pallets? This decision will also revolve around your composting strategy: passive or active. Passive is just leaving a well built pile to do its thing. Active is turning the heap and making compost quicker.
- Build your initial pile in layers. Just as if you’re making a lasagne or even a trifle (but don’t add brandy). The bottom layer should consist of twigs and sticks; these are to provide airflow up and through the compost. Then layer alternating layers of green or brown material with the last top layer being brown. Between layers you can also add natural activators such as soil, old compost, animal manures. Water generously between layers.
- If you’re doing an open heap, build this to a height of sound 1-1.5m. Any higher and it will be difficult to manage. Any smaller and you don’t get a critical mass to generate good heat.
- Keep your heap moist – think of a wrung out sponge. Too wet and it will go anaerobic and smelly. Too dry and it will be very slow to compost.
We prefer to build or place our bin on top of soil. This way soil microbes and other critters can come up from the soil into the heap and help with the composting process – your heap should have a diverse range of critters hanging in there. Also, any leachate will be absorbed by the soil and build soil health.
- After about two to three weeks turn your heap. This mixes the brown and green together and also re-oxygenates the contents. If you have a three bin system, simply turn the material from your first bin into the second, middle, bin. You should notice that the heap is hot. It should not be too dry – add water if it is. And it should have started turning brown and crumbly.
- Repeat the process. Big bits can go back into the first bin to form the bottom layer. Let his heap cool down and then use as you wish. Your compost is ready when it no longer gets hot and when its dark crumbly and smells of Earth.
The whole process should take 12 to 16 weeks. Longer if you don’t turn so much. But hey, “what’s the rush?”.
That’s about it. So what about some do’s and don’ts…
The Dos and Don’ts of Composting
Do add organic paper and cardboard, dog hairs, old cotton briefs or jeans, even stuff from your vacuum cleaner or lint from your dryer (organic only). You’ll be surprised at the vast amount of stuff you can compost.
Don’t add animal faeces to the bin especially if you’re going to use this compost in your vegetable garden.
Don’t add meat, cooked food, dairy. Unless you’ve passed this material through a bokashi composting system first.
You can also feed your compost to an earthworm farm. This is a great solution for people who live in a small space. Unless you’ve used a bokashi system for all your food waste, you should be careful of adding cooked and acidic food to your worm bin – basically, earthworms love fresh green peels from fruit (not citrus), salad greens and other fresh food.
The key is just to start. Keep the balance right. And don’t rush.
When in doubt, remember “compost happens”