Composting is easy and once you learn the basics you’ll be hooked as you transform your food and garden scraps into ‘black gold’.
With less greenhouse gas emitting waste sent to the landfill, and more nutrient rich soil for your plants, you’ll be doing something good for the planet while creating a project that can be fun for the whole family.
What is composting
Composting is the process of decomposing organic solid wastes into nutrient-rich humus. There are many methods to achieve this, with options to suit any type of home and any yard size.
Soils that receive regular doses of healthy compost have better water retention, drainage and aeration, and encourage an environment of helpful micro-organisms. The plants that grow in this nutrient-dense soil will have more resistance to pests and disease and a higher nutritional value.
Hot compost versus cold compost
Hot composting is more involved than cold composting, but will produce compost more quickly—in several weeks to several months. A hot pile requires that specific temperatures and moisture levels be maintained, along with the right balance between nitrogen, carbon and oxygen. This involves regular turning of the mixture, and adding the right amount of green and brown ingredients, and water.
If built correctly, it will heat up within 24 to 36 hours to the ideal temperature of 141°F to 155°F (weed seeds and disease pathogens die at these temperatures) and will maintain its temperature for several days to a week or longer. A compost thermometer can be used to monitor the temperature. If the temperature starts to drop or if it gets hotter than 160°F, turn the pile again and add water. This should be done several times.
A cold pile requires minimal effort but may take a year or two before it produces compost you can use in your garden. You can add your waste as you go, and let time do the rest. The size and types of materials in your pile will determine the time it takes for the compost to be ready. The smaller the particles, the faster they will break down. You will need to avoid putting in weeds that have gone to seed or diseased plants as without high temperatures to kill them off, you will be spreading these around your yard.
Types of containers
For smaller yards, tumbling or static containers can be a good option. A tumbling container will have the benefit of it’s own turning mechanism, and will halve the time it takes to create a rich, loamy compost. You simply tumble it daily and your scraps turn into soil in a matter of weeks (it may take longer in cold conditions). Equal quantities of dry shredded material must be added to ensure the right consistency.
The classic open-based compost bin has side vents to help circulation and a tightly fitting lid to keep out animals. When using a bin, you also need to add good amounts of dry, shredded carbon rich material like newspaper, leaves or cardboard to stop your compost from getting damp and smelly.
There are many different designs for both options, and various ways to build your own affordable container – simply google to find some creative ideas that you can try.
If money is no object, an indoor electric “hot” composter is another option, and can handle up to 2.5 kg of food per day. Unlike other composters, this model can handle meat, dairy, and fish, and turns them into compost within two weeks.
If you have a larger yard, you can you make a simple compost bin from a roll of chicken wire, wood pallets, scrap lumber or cinder blocks. If you’re not that handy you can simply form a pile, preferably in the shade where it won’t dry out.
The location of your compost bin, the blend of ingredients used and turning it are all key elements to successful composting.
How to create your healthy compost
1. You will need to create layers, alternating your green and brown matter. Micro-organisms need nitrogen to break down the carbon. Green (nitrogen rich, wet) materials include your fruit and vegetable scraps, grass and green plant clippings, crushed eggshells, used tea, coffee grounds, old flowers and chicken, horse, camel or cow manure. Browns (carbon-rich, dry) are your dry leaves, small branches, straw, dry grass, shredded cardboard and newspaper, wood chips and sawdust (from non-treated wood).
2. Start with a bottom layer of mulch, twigs or straw, for good aeration and drainage, followed by alternating green and brown layers. Try to add 1 part green to 2-3 parts brown matter when layering. The smaller the items are, the more quickly they will decompose. Adding a thin layer of soil to your green layer adds micro-organisms to get the heap started quicker but is not essential.
3. Avoid putting any diseased plants, pet droppings, cooking fat, glossy paper, biodegradable plastics, disposable cups, weeds and seeds, treated timber and large branches in your compost bin. Also avoid adding any meat, fish, bones and dairy unless you have a larger compost system. Meat, fish and dairy may be composted in a Bokashi bucket (see below) or an electric composter. Also try to limit the amount of citrus peel, onions and bread you put in or just give it to the chickens or worms.
4. Turn the compost with a fork every few days or at least weekly. You can also place garden stakes or plastic pipes through the pile to allow air to circulate. Check moisture levels and add water while turning. You want your compost moist but not saturated.
5. To keep in the heat and moisture, place some shredded newspaper, a tarp or moist hessian sacs over the top. Heat is essential to the composting process and will kill pathogens and weed seeds. If the pile doesn’t heat up, it might be too small or might need turning or watering. You may also need to replenish the nitrogen content of your pile with fresh green grass clippings, garden weeds, kitchen scraps, manure, or an activator, as fast-working microorganisms can quickly consume all the nitrogen and leave undecomposed carbon materials behind.
Compost should take between 6 weeks to 4 months to mature, depending on the method used and how vigilant you are in turning the pile. You’ll know it’s ready when it is dark brown and crumbly but still moist, and most of the original material is unrecognisable. This earthy smelling material is called humus and is full of beneficial nutrients and micro-organisms for your garden.
Troubleshooting tips for your compost
Dense or water-logged compost piles don't contain enough oxygen for the microorganisms to survive. Often these piles give off an unpleasant odour. The solution is to aerate the pile and add more dry materials.
If your pile smells like ammonia, it may contain too much nitrogen. Add carbon materials such as straw, leaves, or hay to correct the balance. Turning regularly will help ensure it has enough oxygen. If it’s too wet, you can pull it into an open pile and add straw and manure.
Finished product is too coarse
Some materials, such as eggshells and corncobs, take a long time to break down. If you want finely textured compost, chop the materials before putting them into the bin. You can also sift out larger chunks and throw them back into the next pile.
Not breaking down – powdery or grey mould
Your pile may be too dry or lacking in nitrogen. Fix the problem by turning and watering your compost. You might also need to add more kitchen scraps, manure, green leaves or lawn clippings. Adding some good active compost or compost starter liquid/spray might also be helpful.
Ensure your lid is tightly sealed, and cover every load of scraps with straw/leaves. Your pile may be too wet or not hot enough. Turn your compost and add bulky carbon materials (straw, woodchips).
Ants or cockroaches
Your pile may be too dry – try adding water and turning. Adding more kitchen scraps, manure, green leaves or lawn clippings should help, or some good active compost or compost starter liquid/spray.
Mice/rats or other animals
Seal your compost bin and line the base with chicken wire. Cut scraps up smaller, and don’t add meat, dairy or fatty food.
Worm composting (vermiculture)
Ideal for smaller spaces, worm composting requires little effort, and produces a fantastic liquid fertilizer that can be diluted with some water and used to feed plants. There are a variety of setups that will work, ranging from clean and convenient store-bought containers to easy home-made designs.
With the colder winter temperatures in Alice Springs, your worms will hibernate if left outside. If the temperature falls below zero degrees then they can freeze. To help keep the heat in, you can cover your worm farm with hessian or carpet, or move them to a more sheltered position. If you have an active hot compost pile you could put some worms in it during winter, although worms in your compost during summer might die. In summer pay particular attention to keeping your worm farm constantly moist, cool and out of direct sun. Ensure garden beds are moist and mulched before adding worms or they will dry out and die. In the warmer months, your worms will wake up and new worms will begin to hatch.
Bokashi buckets allow you to compost your daily food scraps and make liquid fertiliser reasonably quickly, with minimal space, mess, time and energy. The contents can be added directly to the garden, or added to the worm farm or compost container to speed up the decomposition process.
Bokashi composting uses fermentation to anaerobically (without air) break down the material. A layer of vegetable scraps is placed at the bottom and then a layer of Bokashi mix (typically wheat bran, rice husks and sawdust, sprayed with micro-organisms) or a home-made mix is added. Home-made recipes can be found online, using anything from rice bran, wheat husks or wheat bran, saw dust, oats, barley, wood chips or even peanut husks. This layer has micro-organisms that will help the fermentation process and stop the food from smelling as it ferments.
Food scraps are added as you collect them, adding a layer of Bokashi mix each time. When the bucket is nearly full, let it ferment for 10 - 14 days without opening the lid. Drain the liquid every other day and dilute it with water and use it in the garden. After 2 weeks, the contents of your Bokashi bin can be added to your compost pile, garden or worm farm, or placed in a hole dug in the ground where it will continue to decompose and add nutrients to the soil.
For more on the benefits of composting and tips on how to use your compost check out our other blog post on The Joys and Benefits of Composting.