Welcome to COMPOSTER Connection, a comprehensive source of information on the making and using of compost. The Connection provides first-time composters with everything they need to know to get started and be successful. Experienced composters will find new techniques and detailed information on the practice and science of composting. Whether you’re a serious gardener with a desire for large quantities of rich, soil-enhancing compost, or a homeowner who wants to keep your yard and kitchen scraps from the landfill by turning them into nature’s best soil amendment, COMPOSTER Connection is the place for all things compost. Just getting started? Go to the “Making Compost” section listed at left for the basics. Ready to jump in? Visit Planet Natural for our complete line of composting bins and tumblers, tools and supplies.
In the Bin, the Garden, and the Environment
As I began research for this article, my questions merely multiplied. Some of the claims made about compost seemed too good to be true and others made no sense at all. How could compost fight plant diseases? What did it mean to say, as so many sources do, that compost “buffered” or “balanced” soil pH levels? If compost did bind nutrients in the soil, how did it do so? Lots of sources list “adds beneficial micro-organisms” under compost benefits; did it really do this, and if so, what are the benefits?
And then there were the practical questions. Many sources said to layer ingredients for a pile — why? What was the simplest bin for the manually un-dexterous (me) that would still look good? Was there any way to get out of turning a pile? (If so, I wanted to know about it.) What advantage was there to hot composting, other than speed? Some sources said a hot pile would kill weed seeds; others said to keep weed seeds out of the pile. How hot, then, did a pile have to be, and for how long, in order to kill seeds? What about pathogens? Oh, and was it possible to add too much compost to soil?
In writing this article, therefore, I wanted to cover the nuts and bolts of composting as thoroughly as possible, but I also wanted to answer those questions about how compost does what it does, which meant delving into compost physics, chemistry, biology, and soil science. For those who share my insatiable curiosity, I’ve included most of the scientific information I came across, but in deference to those who want to get started on a pile without wading through all kinds of background information, the science is largely confined to its own sections.
As it turns out, all those claims about what garden compost can achieve are true. Compost suppresses soil-borne diseases? True. Compost prevents nutrients from leaching out of soil? Also true. So are the claims about beneficial micro-organisms, for which I feel a new and probably unrequited affection. And the claims about “balancing” soil pH, which turns out to mean that compost will help raise pH if it’s low and lower it if it’s high. Not to mention the claims that it improves water retention in sandy soil and water drainage in clay soils.
And that’s just the start.
Benefits of Compost to Your Garden
• improves soil structure in all soils, and therefore
• improves water retention in loose, sandy soils;
• improves drainage in heavy, clayey soils;
• prevents the soil surface from crusting, easing the emergence of seedlings;
• resists compaction, making it easier for roots to penetrate the soil;
• helps balance pH, making alkaline soils more acidic and acidic soils more alkaline;
• provides a good environment for the microbes, earthworms, and insects that break down soil constituents into plant nutrients;
• nourishes microbes that protect against some plant diseases;
• reduces the need for other soil amendments and for fertilizer;
• provides many micro-nutrients and low levels of macronutrients;
• raises the cation exchange capacity (CEC) of soil, which means that it also
• improves the soil’s retention of nutrients, thus increasing the amount of time they are available to plants;
• slows the leaching of nutrients, thus preventing them from reaching and polluting water;
• encourages healthy plants, thus reducing the need for pesticides and fungicides.
Benefits to the Environment
• reduces the amount of garbage in landfills, and therefore
• reduces the greenhouse gases produced by hauling garbage;
• reduces the amount of methane produced by landfills;
• helps prevent runoff and soil erosion;
• helps remediate (decontaminate) polluted soils, binding some contaminates in the soil and increasing plant uptake by others, allowing their removal from contaminated sites;
• reduces the need for environmentally damaging pesticides and fertilizers.