I listened to a really good podcast the other day about the amount of food that gets wasted between the farm and the plate. You can listen to it here. It's not very long and you may be incredibly surprised at some of the statistics... like that one third of all food grown in the world is not eaten, that Australians throw away enough food each year to fill 450 000 garbage trucks and that the amount of greenhouse gas produced in Australia from decomposing food waste is the equivalent of what is produced in the manufacture of iron and steel. Excuse me while I pick my jaw up off the floor.
The impact of the loss goes beyond the fact that consumable food is thrown away - the resources that go into that food are lost too. Did you know that 1 kilo of rice grown here in Australia requires over 1500 litres of water to make it to your plate? When food is thrown away, you are throwing away far, far more than just the food itself and the impact when compounded across the food production, the transport, the processing, the retailing, the purchasing, the preparation and then the lost product is staggering when you actually sit down to look at it. And that's all before it ends up in an anaerobic, stinking state of decomposition in landfill adding to our methane emissions.
The solution, of course, is to not be so wasteful and have more respect for the food we purchase, to prepare and consume it more mindfully and completely, and to commit to not placing ANY food in landfill...but this is not something that can be cultivated overnight after a lifetime of habit in a culture where food is not particularly valued (we have plenty of it, right?) and our garbage and waste is not something we have to deal with beyond dragging our wheelie bins to the roadside each week and paying a waste levy in our property rates. So, what to do?
Enter, the importance of compost.
In the market garden we just left, we were blessed with an endless supply of highly nutritious compost. It was an excellent opportunity to see just how much difference compost actually does make to the health of plants and the amount of produce harvested. We managed to grow an amazing amount of pumpkins, potatoes and watermelon on soil that was pretty much just powder, by adding plenty of compost and mulching heavily. The plants were able to get what they needed out of the soil (nutrients and water) to grow and reproduce, and as a result the soil that was there six months later had changed completely - it had structure and was teeming with life. Now, the key to turning that soil around was definitely the plants (plant roots in the soil, whether they are weeds, grass or productive plants, are the basis of life for soil microbes - and soil microbes are where it's at in terms of soil health), but the plants would not have been able to grow so bountifully if they weren't able to access the necessary nutrients they needed. The compost was made on site, and it was the first time in my life that I was placing nothing 'organic' into the bin. The amount of waste was significantly less, and it was such a good feeling to know that the veggie scraps, egg shells and tea bags were being put to use to grow me food rather than rotting in a pile. (As an aside, when we moved back to town I was excited to see that our local council had just implemented a new waste collection strategy where all organic waste, including greasy cardboard, animal droppings, garden waste, kitchen scraps and meat bones could be placed in the green-lidded bin and collected weekly to be taken to a new facility that composts the waste. Super cool).
When people ask me for advise on integrating permaculture into their home garden and lifestyle, one of the very first things I think of is "how can I get them composting?". Often this means I will encourage them to start a worm farm, or integrate temporary worm towers in garden beds, because worm farms seem a little simpler to explain and implement. But in my opinion, you need both a worm farm and a compost bin to be really cranking along in the closed-loop food production stakes.
Unfortunately, composting can seem hard, and technical, and a bit scary before you start and I think this is where most people are put off. It needn't be any of those things - below are some tips, resources and myth-busting to get you thinking about giving composting a go:
- Place a dedicated bucket or composting receptacle in your kitchen, and put any food scraps, egg shells, coffee grounds, tea bags, paper towel in it. You can get nice ones now!
- When it's full, take it to your outside composting spot. This could be a homemade bay, ring or simple pile, or a store-bought composting bin depending on your budget and space.
- Chuck your scraps in and have a look at what you've just added - is it mainly scraps and 'wet things' (nitrogen)? If it is, you need to add some dry material (carbon) to balance it out. You could add dried leaves, straw or shredded paper. Just make sure it's finely shredded and that the straw is not in big clumps - you want it all to be able to mix in together. Aim to add enough carbon-material to cover the nitrogen-material. As a general rule, always add slightly more carbon than nitrogen. (Composting wisdom tells you that you need a specific ratio of Carbon to Nitrogen to have a balanced and non-stinky/slimy compost pile - I say forget that rule, just chuck it in and adjust as you go along).
- Common consensus is to not add things like meat scraps or bones to your compost pile. This is not because they won't compost or be beneficial, it's mostly to do with not attracting vermin to the compost. Use your own judgement here. If you don't think it will be a problem to add these things in in your space, then go for it!
- Avoid cat poo in your compost - it has potentially nasty health implications.
- Other animal manure is often best composted before being used, especially if it's coming from animals treated with conventional worming treatments and the like. It's an excellent addition to your compost pile...
- ...as is road kill. Yep. Just make sure you bury it in the middle of a large pile to avoid the stench, and maybe don't go down this route in your very first pile :)
- Compost needs aeration. This means you need to turn it using a garden fork or a specific compost spiral if you have a stationary pile, or that you need to regularly 'tumble' it if you have a tumble-composter. You could also place an aeration pipe in the centre - check out this tutorial.
- Adding activators to your pile will heat it up and make it break down more quickly - comfrey and grass clippings are golden for this.
- The other thing you need for good compost is patience. You can build a hot compost pile (best for composting any weeds with seeds) and have it finished in a couple of weeks in the right conditions if you are prepared to build it all at once and tend it well over that time. For anyone wanting to just deal with their household waste on an ongoing basis, you need to be prepared to let it take as long as it takes - and the added bonus to this is that you end up with a complex end product that's had a huge variety of additions to it.
- Finished compost won't leach out nutrients - but if you have a slowly decomposing pile you may want to cover it so that it doesn't get too wet and to help retain heat.
There are stacks and stacks of resources out there teaching you how to make compost. Take a look at them, get a feel for it, then play by your own rules. Compost is a fantastic addition to your 'permaculture' system or any garden for that matter - your plants will love you for it, and you can feel better knowing that any uneaten food you do need to through out is not entirely wasted.