Compost Info Guide

Compost Tips, Composting Aritcles, Compost Bin reviews and much more...

Composting Articles:

Brown Composting Materials

Composting relies on the right ingredients to be successful. Brown materials such as leaves, straw, hay and sawdust are high in carbon and are a source of energy for the compost microbes.

Leaves (50-80:1)

Leaves are generally an excellent ingredient for your compost. Those living in areas with a large bounty of autumn leaves should make the most of it and find some neighbours willing to pass on their leaves. Many neighbours will do the raking for you if you agree to cart away the piles!

Living green leaves are considered "green materials", wheras the dead, dry leaves that fall from the trees in autumn are seen as "brown materials".

Autumn leaves are a great source of carbon and contain a surprising amount of nutrients that can be returned to the soil through compost. Although whole leaves are acceptable, it is better to shred the leaves before adding to the compost pile. Unshredded leaves tend to mat together excluding air from the pile. Leaves can be shredded in a number of ways:

  • using a commercial shredder or chipper
  • by pushing a lawn mower back and forth over a pile of leaves a few times. The use of a mulching mower blade will help.
  • shred leaves in a large garbage can with a lawn trimmer

Remember to wear eye protection regardless of the method you choose.

There are a few types of leaves that need special attention when composting:

  • walnut leaves contain a substance that inhibits the growth of many plants. As a result, walnut leaves should either be very thoroughly composted or omitted altogether
  • oak leaves take a very long time to break down because of their acidity and high levels of tannin. They will break down into a wonderful amendment for acid loving plants but it will take much longer than with other leaves. It is often a good idea to keep them separate to allow the main compost pile to finish sooner. A separate pile can then be made of oak leaves that can be used for plants that prefer an acid soil.
  • Waxy leaves also take longer to break down such as those of the holly, laurel, rose, pine and rhododendron. They are often best composted separately

Legume Hay (15:1) and Non-Legume Hay (30:1)

All types of spoiled hay make an excellent addition to the compost pile.

Straw: (80:1)

Straw provides less nitrogen than hay but contributes more than double the carbon. Straw decomposes quite slowly so it's an especially good addition in areas with heavy clay soil. The remaining straw particles in the finished compost help to open up the soil structure.

Paper & Cardboard (150-200:1)

Paper such as newspaper, bills, paper towels, tissues can be composted but it should be shredded first. Avoid adding glossy and highly coloured papers. Stiff cardboard should be broken into small pieces or made into a slurry before it's added to the pile.


Eggshells contain calcium and are a useful addition to the comost pile. The shells do take a long time to break down so it's a good idea to crush them before adding. Do not include whole eggs in your compost, just the shells.

Tea Bags

Both black tea and herbal teas can be composted, whether loose leaves or in bags.

Sawdust* (400:1)

Sawdust and wood chips contain very low amounts of nitrogen and are very slow to break down in the compost pile. Use sawdust in very thin layers or mix thoroughly with a green material such as kitchen scraps or grass clippings. Large wood chips will take a very long time to break down and are often put to better use as a mulch.

*Be careful not to compost any sawdust or wood that has been "pressure treated" or otherwise treated with a chemical preservative. Pressure treated wood (often recognizible by a greenish tint) has been shown to leach arsenic into the soil when used for making playground equipment, compost bins and raised beds. For more information see the section on "what not to add to a compost pile".

Wood Ashes (25:1)

Wood Ashes are an excellent source of calcium and potassium but are also very alkaline. Use sparingly to avoid high pH levels that limit microbial activity. Avoid composting charcoal briquettes as they take too long to break down. Also, avoid composting the ashes created from commercially made "firelogs" which often contain wax and other petroleum derivatives.

Next Page: What not to Add »