Compost is a natural process through which organic material is converted into a soil-like product or humus (pronounced “hue-mous”). The process works with the help of micro-organisms such as bacteria and fungi combined with air and moisture.

Compost is an important way to recycle and can be done at home. It is an easy way to reduce the amount of household garbage by about one third. As well, it produces a valuable soil amendment for use in gardening and landscaping.

What’s In the Mix?
Most household organic waste can be composted at home. For backyard or home composting to work best, it is important to use selected material including:

From the Garden…
Leaves (chopped – to speed their breakdown)
Grass (not wet)
Plants & Weeds (without ripe seeds)
Old potting soil
Soft plant stems

From the Kitchen…
Fruit scraps
Vegetable trimmings
Egg shells (crushed)
Tea bags
Coffee grounds with filters
Shredded paper

DO NOT include…
Meat, fish and bones
Plastics
Metals
Fats and oils
Dairy products
Pet waste
Cheese, meat or other sauces

Home composting can be done with the use of a “build your own” or with a commercial unit, often available through your municpality.

An important first step to getting started is to place your composter in a sunny area with good drainage. Make sure that the location is convenient and accessible year round.

Getting started…

• Turn the soil in the location where the composter will be.
• After placing the composter, cover the floor of it with a layer of small branches. This will allow for air movement and drainage.
• Alternate wet (e.g. kitchen scraps) and dry (e.g. yard material) waste.
• If available, add some “finished” compost, garden soil or a compost starter (available at most garden centres) to the pile. This helps speed up the start of the composting process.

• The composting process works best when the organic pieces are small. Weeds and trimmings should be shredded.
• Don’t add thick layers of any one kind of waste. Grass should not be more than 6 cm deep, leaves up to 15 cm deep (cut or chop or dry and crumble them). If you can, let grass dry first or mix it with dry, coarse material such as leaves to prevent compacting.
• The composter contents should be moist like a wrung-out sponge. If the contents are too dry, it will take overly long to compost; and if too wet, the contents may begin to smell.
• Turn or mix the compost every couple of weeks or each time you add new material. This keeps the compost well aerated.
• Composting can be done in the winter. You can add materials to your composter all winter long. The breakdown process slows down or stops when the pile is frozen, but it will start up again in the spring. Thorough turning in the spring will reactivate the pile. Empty the composter in the fall to make plenty of room.

Troubleshooting
Composting is not difficult but sometimes the process requires a little extra attention. Here are some easy solutions to correct certain situations which might occur.

• If the pile does not decrease in size or generate heat, composting may need a boost. If the pile is dry, add water – mixing thoroughly. If the pile is wet and muddy, spread it in the sun and add dry material. Remember to save “old” compost to mix with incoming material.
• If the centre of the pile is damp and warm, but the rest is cold, the pile may be too small. Try to keep your composter as full as possible. Mix new with old, dry with wet, breaking up mats and clumps.
• If the pile is damp and sweet smelling but not heating, it may need nitrogen. Add grass clippings, table scraps or a sprinkling of organic fertilizer from the garden centre.
• If the compost pile develops a foul odour, it may not be getting enough air. Loosen up the pile, break up clumps, unblock vents and perhaps add some wood chips to help the pile “breathe”. Turning the pile always helps aeration.
• Compost in a container with a cover to prevent animals from getting into the composting materials. A wire mesh around the base can help to prevent pests from digging under the pile. Dig in or cover food waste immediately.

Is It Finished Yet?
The composting process can take from 2 months to 2 years, depending on the materials used and the effort involved. To accelerate the process, the pile must be a balance between wet and dry material, turn it frequently and make sure the waste is shredded or in small pieces.

Compost is ready to be used when it is dark in colour, crumbly and has an “earthy” smell. You can sift the compost to eliminate material which has not yet finished composting. Return this back to the pile to complete its transformation into humus.

Put Compost to Good Use
Composting can benefit your soil and plants in many ways. It increases the soil’s organic matter content and its moisture-holding capacity. Compost improves soil porosity and helps to control soil erosion. It also enhances plant and flower growth and helps plants develop a sound root structure.

Use it on your lawn, in your garden, around trees or combine it with potting soil for your plants.

Written by
Susan Antler
Executive Director, Compost Council of Canada

The Compost Council of Canada is the national non-profit, member-driven organization dedicated to advocating and advancing organics residuals recycling and compost use. The Council serves as the central resource and network for the compost and organics recycling industry in Canada and, through its members, contributes to the environmental sustainability of the communities in which they operate.