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Ways you can compost your food waste

Hannah Moloney loves the magic of composting. Picture: Good Life Permaculture.

Hannah Moloney loves the magic of composting. Picture: Good Life Permaculture.

Food waste composting can be a baffling affair, but it doesn't have to be. In fact, it can be glorious and even slightly magical. There are a few different ways you can make this magic happen to turn a big food waste problem into a great solution for your garden.

Keeping food scraps out of landfill and returning them to the Earth isn't just about benefiting your vegie patch, it's also wonderfully effective in preventing methane emissions - a toxic gas up to 28 times more harmful than C02. So when you're composting, you're taking part in a meaningful climate solution.

But some people might have had a crack at composting in the past and thought, composting is so stinky - it's not for me. Here's the thing, if your compost stinks, it's actually not compost. It's just a gross stinking pile of most likely, rotting food waste. Good compost doesn't smell bad.

Ready to start composting?

There are four universal compost ingredients that every single compost has, but may configure slightly differently - they are: carbon, nitrogen, air and water.

Successfully making compost comes down to getting the balance right, especially the nitrogen to carbon ratio. Too much nitrogen and it will become gross and stinky, this means your compost has turned anaerobic. You need to balance it out with carbon materials like dry brown leaves, straw, sawdust, shredded office paper or cardboard, but never use glossy magazines because there's too much ink in the paper.

Common nitrogen materials you might have around the home include grass clippings, some animal manures (but never pet waste as they can compromise compost used for food gardens). But of course the main nitrogen materials for the home compost is food waste.

The great thing is, you can pretty much compost everything that was once alive, that includes coffee grinds, cooking oils, bread, plate scrapings from meals and even small bits of meat - but don't go chucking big bones in there, they will just sit there forever.

Chop your food scraps into small pieces where you can, as large pieces will take ages to break down. So when you're in the kitchen preparing a meal, just take an extra 10 seconds to chop up the scraps.

As far as things that you really shouldn't chuck in the compost, there are a few. Weedy plants, like runner grasses, oxalis and seeds from invasive species aren't a good idea. Also keep sick or diseased plants out of your compost, instead bin or burn them. Also, some tea bags have polypropylene plastics in them and are no good for your compost, so be sure to check your brand.

Getting started

Start your compost with a decent layer of carbon, so that it can absorb any liquids that soak down, something like straw is great. Make it nice and fluffy to get lots of air inside your compost bin. Water in after every carbon layer to keep a nice moisture balance.

A tip to remember when you're making a whole layer of materials is to make your carbon layer roughly one full-hand depth and the nitrogen layer, like grass clippings, roughly one-pinky-finger's depth. So one pinky of nitrogen to one hand of carbon - the carbon will squash down as more weight goes on top.

Continue layering up like a lasagna, repeating a carbon layer on top of a nitrogen layer, remembering to add a bit of water to the dry carbon layer as you go. Once you've got a couple of layers of carbon and nitrogen started, go ahead and add your food scraps.

When adding your food scraps always add about the same amount of carbon material to balance it out. Also, covering your food scraps in a carbon layer each time you add them to your compost will help keep the flies and any bad smells away.

If you find your compost doesn't seem to be doing anything, it's not composting or breaking down, it might be too dry, so add a little water, or some chicken poo if you have it. Or if it's a bit stinky, increase your carbon material.

Worm farms

Another way to compost kitchen food waste is with a worm farm. But worm farms can only house compost worms, not your common earth worm - they will die. Compost worms are red wrigglers and tiger worms, which you can buy from most nurseries.

In one worm, there are around 474,075 million bacteria, which do an incredibly important job, mainly making minerals available. When compared to the parent soil (the original soil), worm castings (the worm's poo) have approximately: seven times the available phosphorous, six times the available nitrogen, three times the available magnesium, twice the available carbon and one and a half times the available calcium.

But worms don't magic these minerals into existence, they were already present in these quantities - but by digesting them, the worms make the minerals more available to plants in a soluble form. Catching the worm castings and using them as fertiliser for food crops, is why people have worm farms.

There are lots of ways to create a worm farm in your own backyard, from wheelie bin worm farms to building your own worm farm bench seat using a bath tub. It is a true beauty and, when designed properly, can double as a table for potting up or doing garden jobs on. The bath tub also makes it easy to catch the worm-wee fertilizer.

Worm towers 

If you're tight on space, a worm tower is another way to get worms involved in your composting and can be a nice compact solution to fit into smaller spaces. A worm tower can be made from lots of different things, including an old bucket with a lid.

To get started, drill holes into the bottom and sides of your bucket big enough for a worm to squeeze through. The reason for using a bucket is to keep the rodents out.

Dig a hole almost a deep as your bucket into your garden, vegetable bed or raised garden bed. The idea is that it will provide fertility where it's needed most, so right next to that carrot root or tomato plant. Back fill the bucket with soil and straw, or mature compost or other quality garden soil to create a neutral layer to add the worms.

Add your compost worms and then add your food scraps and finish with a layer of carbon to keep the flies away. Pop a lid on top to moderate rain and keep rodent out and that's your worm tower complete. The worms can come and go through the holes as they please.

There are a million and one more ways to compost your food scraps - the main thing is that you actually start; that you do it; and watch how you get addicted to it. It's so satisfying when you can turn those banana scraps and pumpkin peels into incredible, beautiful brown compost that you can use to grow your own amazing food - while also helping the planet out.