The idea of starting a compost pile, or buying or building a compost bin, is daunting for many people – and for no good reason that I can see. The simple point is to get organic matter into our soil, which tends to be clayey and lacking in organic matter, in whatever way we can.
We can either put the organic matter directly into the soil, or we can pile it up and let it break down and decompose awhile until it’s a humus-like material we call compost. The whole deal needn’t be daunting. In fact, it’s exhilarating; this is magic!
What organic matter?
“O.M.,” as its friends call it, is any material that has ever been alive – including wood chips, sawdust, paper, straw, hay, cocoa shells, any parts of plants, animals’ waste (manure), coffee grounds, any food scraps and even dead animals. Cover crops, sometimes called “green manure,” are important tools for soil building – worth a whole book.
This doesn’t mean you necessarily want to use all organic matter in your garden or even your compost. Meat scraps, salad oils or dead bodies attract undesirable animals. Wood chips and sawdust break down so slowly they not only don’t help the soil, they also tie up the soil nitrogen in their slow decomposing process. (Save them for paths or top dressing.)
Now for the organic matter that’s most useful and available, and how to incorporate it:
• Leaves: The simplest form of composting happens in a leaf pile. If you can make a heap of leaves – ideally 3 cubic feet – in six to 12 months it will become “leaf mold,” a common gardening term for leaf compost. (A smaller pile will eventually decompose, but it takes a certain volume before microorganisms activate and create enough heat to really get the process going.)
The alternative to composting leaves is just to chop them up with the lawn mower and put them into or on top of your soil. If you allow the leaves to remain whole, they will eventually break down as well, but it’s slow; oak leaves take the longest. I put whole leaves in the compost pile and chopped or small leaves directly on the garden as mulch.
• Yard waste (sticks, debris): Limbs are too big to compost and should be left in the woods, built into a brush pile for wildlife or, in urban settings, put on the curb to be carted away – depending upon the practices of your city or town. Some towns make wood chips or compost available to citizens. Sticks and twigs, however, up to one-half-inch thick, are great additions to the compost pile. Use them in 2- or 3-inch layers, alternating them with leaves or other material.
• Pine needles: I go out of my way to pick up bags of pine needles, as I love their look as a mulch (on top of the soil) and they are equally useful in the compost or turned into the soil. People often worry that they will make the soil too acidic, but in reality it would take a long time for pine needles to make much difference, and most of our soils are too alkaline anyway. (When it doubt, get a soil pH test through the Cooperative Extension.)
• Kitchen scraps: If you live in a suburban or rural area, where composting is permitted, then you can add kitchen scraps to your list of compostables. (You will hear concerns about the food attracting rats or other animals, but if you bury such food materials – never meat – a foot beneath the surface it should not be a problem. )
You need to figure out your own method for collecting and holding kitchen scraps. Garden stores often sell table-top collecting bins (with a charcoal filter), but you can also use milk cartons or a covered pot to gather vegetable and fruit scraps, egg shells, fruit rinds, banana peels, coffee grounds, tea bags and spoiled salad greens. Include fallen houseplant leaves or clippings as well.
Periodically take your collection out to the compost pile. Or do as Grandma did, and put the potful of scraps into a hole in the garden, and bury it 8 inches deep, moving along hole by hole, day by day. In winter, some composters freeze their kitchen scrap collections in a garbage can or heavy plastic bag outside, and move it to the compost pile during a thaw.
• Manure: If you are lucky enough to have access to manure, nothing helps a compost “cook” faster. Just layer a couple of inches of it, alternating with leaves, food scraps or twigs. You can also turn manure into your garden hole by hole, or you can layer it on the garden in fall and turn it under in spring. Manure should always be aged – preferably nine months or more – to be sure it’s not too “hot.” Fresh manure literally burns growing plants.
Which manure? The manure you can get is the best one. My garden benefited from horse manure for many years, with the downside that it usually comes with many weed seeds. (You’ll have to hoe the seedlings or mulch over them.) I have also enjoyed equal successes with guinea pig bedding, composted before using. Chicken, cow, sheep, rabbit and pig manure are all good, varying in intensity.
• Straw and hay: In case you find a post-Halloween bale on the side of the road, grab it for your garden. Straw is relatively weed-free, and is great to spread now and turn into the garden in spring, or you may prefer putting it into the compost. Hay can be used similarly, but expect weed seeds and have a plan to deal with them. Do not turn seedy hay directly into the garden or you’ll be very sorry you did.
• Shredded paper: Save yourself from identity theft and shred that paper to use as a layer in the compost pile, or turn it into the soil (small amounts at a time).
Making a compost pile is the rest of the story. Try layering the materials that you have, alternating the wetter or green materials with drier, woodier matter, and keep it all slightly damp. You may work with a simple pile, enclose it all in chicken wire or pallets, buy a manufactured bin, or build something more elaborate. Composting is not difficult, and you can’t go terribly wrong. Mother Nature has been doing it for thousands of years.
Sally Cunningham is a garden writer, lecturer and consultant.