See how much compost you'll make and money you'll save
Composting is one of the highest-value things a Canadian gardener can do. Finished compost improves soil structure, feeds soil microbes, retains moisture, and slowly releases nutrients — it does everything a bag of synthetic fertilizer does, plus a dozen things fertilizer can't. A 2-inch layer of compost worked into your raised bed each spring is often all the nutrition most vegetables need for the entire season.
Canadian winters actually help composting — freezing and thawing breaks down organic matter faster. Your compost pile may slow down or stop in January, but it picks up rapidly in spring, often producing finished compost just when you need it most — right before planting season.
You can compost fruit and vegetable scraps, coffee grounds and paper filters, tea bags, eggshells, grass clippings, leaves, small branches, shredded newspaper and cardboard, and garden trimmings. Avoid meat, fish, dairy, oily foods, diseased plants, and pet waste — these attract pests and create odour problems. Many Canadian municipalities also offer green bin programs that accept meat and dairy, so check if your city has one as a supplement to your backyard compost.
In Canadian climates, a hot compost pile that you turn regularly takes 2–3 months in summer. A passive pile that you just add to without turning takes 6–12 months. The cold months slow things considerably, but your pile will still break down — just more slowly. Many Canadian gardeners start a pile in fall (adding leaves and garden waste) and have finished compost by June. The freeze-thaw cycle actually helps break down tougher materials like cardboard and stalks.
The ideal ratio is roughly 1 part "greens" (nitrogen-rich materials) to 2–3 parts "browns" (carbon-rich materials). Greens include food scraps, fresh grass clippings, and garden trimmings. Browns include dry leaves, cardboard, newspaper, straw, and wood chips. Most home composters have too many greens and not enough browns — this causes a wet, smelly pile. Keep a bag of dry leaves or torn cardboard nearby to add whenever you add food scraps.
Finished compost is dark brown or black, crumbly, and smells earthy — like a forest floor after rain. You should not be able to identify the original materials. If you can still see food scraps or recognizable plant material, it needs more time. A simple test: fill a bag with some compost, seal it for a few days, then open it. If it smells fresh and earthy, it's ready. If it smells bad, it needs more time to finish breaking down.
Apply a 2–3 inch layer of compost to garden beds each spring and work it into the top 4–6 inches of soil. For raised beds, this is usually all the fertilizer light and medium feeders need for the season. For in-ground gardens with poor native soil, you can apply compost both spring and fall to build up soil organic matter over time. Use our Fertilizer Calculator to see exactly how much compost your bed size needs.
Insulated compost bins work best for Canadian winters as they retain heat longer and keep the pile active into late fall. Black plastic bins absorb solar heat and can stay active well into November in most parts of Canada. Tumbler-style composters are also popular because they're easy to turn and can be positioned to catch maximum winter sunlight. In spring, simply open the bottom of any bin — the finished compost will have settled to the bottom over winter, ready to use.
Put your finished compost to work in the garden.