How To Set Up Your Own Home Composting System: All Your Questions Answered

Learn how to compost at home with these easy-to-follow expert tips from Grow Inspired's Claire Mummery

It's easier than you think to compost at home. Photo / Babiche Martens

Claire Mummery from Grow Inspired is an expert in organic gardening, waste management and circular eco systems for food growing and composting. Here, we’ve gathered her top home composting tips.

Why should I compost?
Did you know that around 122,547 tonnes of food waste goes to landfill each year in New Zealand, which equates to $872 million worth of food? In landfill, it simply rots and produces harmful methane gas.

With increasing numbers of us wanting to make a difference, or to grow our own food — whether in a small backyard or lush lifestyle block, it’s important to understand the value of composting. By composting, we can process all our food waste and return this to our soil to increase the value of nutrients and microbes in depleted gardens.

READ: Why Composting Should be Your New Passion

How do I get started?
Start with a can-do attitude and a willingness to learn. Then do some easy research into the kind of system that is going to best suit your set-up at home. Do you have a small or large space? How much time do you have? How much food waste do you produce? Can you process the compost on your own property? Is there a community garden near you? Answer these questions and you’re already on your way.

What kind of compost system do I buy, or can I make one myself?
Bokashi bins in a variety of sizes are available from NZ retailers, with bench-top bins well-suited to urban homes. Worm farms and three-bin compost frames are available in any good garden centre. All compost systems can be made at home for little or no cost. A compost bin for your garden waste can be made from un-tanalised pallets tied together. A bokashi bin can be made with two recycled food grade buckets inside each other — one with holes and one without — and a tight-fitting lid.

Worm farms can be made from poly-boxes, or two stackable bins or buckets — have one with holes in the bottom and one without holes, so the valuable worm juice can drain into this. The poly trays require a lid or thick corrugated cardboard on top. You’ll need 1kg of tiger worms to get started, and you can simply put a request on your community noticeboard or Facebook!

How much time and effort will composting take?
Composting doesn’t have to be a full-scale hobby and, on a daily basis, it is no harder than scraping your food waste into the bin. Depending on your chosen method, there is just a small amount of extra effort required for maintenance. For bokashi, once a fortnight you will need an extra half an hour to put your ‘pickled food’ into garden trenches, pots, or containers so that it can continue its process to break down into soil. For your worm farm, you will need a spare couple of hours once every three months to harvest your invaluable vermicast and pop onto any growing bed to watch the ‘magic’ happen to your plants. For a compost pile, you will use a few hours to turn it once every 2-3 months.

Can you explain the bokashi system in a nutshell?
Bokashi is a process that ferments food waste inside a closed bucket without air (anaerobic), using very clever bacteria known as ‘effective microorganisms’. The bacteria work fast and cleanly to compost your food scraps with no bad odour. After this initial fermentation process, they will look and smell ‘pickled’. Then if you put the scraps directly into the soil, they will continue breaking down and turn into the most nutrient-rich soil, which is an elixir of life for your plants to grow in.

Over the past 15 years, I have done many experiments — small and large scale — using bokashi and have had outstanding results with growing food. The plants are so much healthier, need a lot less watering and the colour of the leaves are so much more vibrant.

I have used it on a large scale at restaurants in turn creating useable soil, building up garden beds and diverting over 19,000 litres of food waste away from landfill over a two year period.

What do I do with my bokashi end-product?
There are many ways to process Bokashi. It doesn’t require a trench to be dug into the garden — you can layer it on top of the soil, as long as you cover it with a carbon material. Either leaves, straw, paper or cardboard. You can then simply put your plants straight into it.

Alternatively, you can process in a compost bin — empty the entire contents of the bokashi bin on to this, covering with another layer of ‘brown’ material.

Keep repeating until it’s full — this can actually take up to three months to ‘fill’ as it’s continually breaking down all the time. When full, leave for 1-2 weeks then empty it straight on to the garden.

Another way is to process it through your worm farm, and the worms will turn the pickled food into vermicast for you. I recommend worm farms to smaller households and those with less space. It’s clean, compact, efficient and you can also feed worms your waste paper and cardboard. If you live in an apartment, you could make a container garden and layer your bokashi in there.

What if I’m not a gardener, is composting wasted on me?
Absolutely not! You might have a friend or a community garden that would love your bokashi or vermicast to grow their food with, or make a really nutrient rich compost. Also remember you are doing your part for the planet by keeping food waste out of landfill.

What’s the biggest misconception around composting?
#1 That compost smells! I guarantee that compost only smells putrid if you are doing something wrong — for example, it could be too wet, too dry, no lid etc.

#2 That composting is difficult! Composting is like anything new where you will need to learn the process, but it will take no longer than learning how to use your new camera or TV — it’s all about approaching with a can-do mindset.

#3 That composting takes up too much space! There are different styles to suit the space you have available — it can be as compact as you want it to be.

What are your top 5 quick-fire composting tips?
1. Always put brown layers either side of your green layers
2. Learn the basics of composting — it will take you 15 minutes of your time and will save a lot of trial and error as you get going
3. Home compost grows more nutrient-rich food, in turn saving you money!
4. Worm farms like the shade, but pallet compost bins need to be in the sun
5. Always cover or put a lid on your compost to avoid unnecessary odours

What’s a good resource for information?
Join a composting, worm farming or bokashi group on Facebook. New members are always welcome, as people love to share their passion. There’s so much info out there — books available at the library, YouTube videos, Pinterest… There are also many council-subsidised courses for beginners available in your local area. I regularly host them on Waiheke Island and I am forever sharing tips in my weekly newsletters and blogs. Start small — focus on one area or one group and, if you do need to Google, be specific in what you want to know to avoid an overwhelm of info…

Remember, composting is fun and so beneficial for your garden, and most of all, beneficial for the planet. Visit for more info, and to sign up to Claire's newsletter with weekly tips on composting, gardening and more.

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