
As part of International Composting Awareness Week, I recently participated in a free composting workshop put on by my local council in the community gardens.
I've always been a fruit and vege scraps collector, but have not really known what to do with them, so I've usually ended up either tossing them in the bin eventually, or tipping them in some inconspicuous garden location. When I saw this workshop advertised, I jumped at the chance to get my hands dirty and find a better way to make use of my scraps. I discovered that there are many different ways to compost, from a small kitchen composting unit, to cold composting in an outdoor compost bin, to worm farms, to hot composting in a huge open pile. I learnt some amazing tips and facts that I would love to share here.
Over 50% of landfill is comprised of food and garden vegetation. This material contributes to green house gas emissions by producing methane due to anaerobic breakdown. Composting is good for the environment because it helps reduce the impact of these emissions, recycles valuable nutrients (therefore reducing the use of artificial fertilisers), conserves water, and improves soil quality and garden vitality. The main difference between composting and landfill is that the material is broken down aerobically rather than anaerobically.
Compost ingredients can be considered in terms of nitrogen rich material or carbon rich material. It is important to get the right balance between the two, with the most common mistake being the use of too much nitrogen rich material.
To make a cold compost in a compost bin you need a bin with a lid and no bottom. Purpose built compost bins are available at your local hardware store or sometimes through your local council. You need to make layers, and keep them going as the pile progresses. Start with a thick layer (about 15cms) of twigs or mulch at the bottom for drainage, then do a thin layer of nitrogen rich material, followed by about 2-3 times the amount of carbon rich material and moisten well. Keep this process going as you collect more and more material and create a heap layer upon layer. Remember to use a diverse range of ingredients.
Add air to your compost by turning it regularly (about once per week), and this helps prevent it from smelling. You want your compost to be moist but not sodden, so if it appears too wet, add some more dry material to it. Adding a little bit of soil on top of food scraps also reduces odour.
Fruit and vegetable peelings, tea leaves, coffee grounds, egg shells, newspaper, human and animal hair, grass clippings, old potting mix, dead plant materials and chicken, horse and cow manure.
Meat and dairy can be composted, but it is best left out until you are an experienced composter. Do not compost manure from meat eating animals.
Self contained in-kitchen composting units can compost animal products and have the advantage of producing a 'juice' to dilute and use as fertiliser, as well as broken down vegetable scraps that can be dug into the garden. There is no need to add any 'carbon' material. This is by far the easiest and most convenient way of composting, but can be expensive. This system works by adding a particular microbe into the scraps to speed up the breakdown process.
To sum up, I found the workshop extremely informative and inspirational, and I'm ready to get cracking on my backyard compost bin! I no longer have the dilemma of not knowing what to do with my scraps, and can rest easy knowing that I am doing something great for the environment, as well as eventually my vege patch!