Waste paper is the answer to a composter’s prayer. just enough water

Soil animals and microorganisms need water. The bacteria and other microbes live in the film of water that covers compost particles, and most soil animals especially worms, the most important ones—are very intolerant of drying out. So obviously the ideal compost pile needs to be at least moist. But not too moist—too much water conflicts with the need for air, and there is no faster route to a smelly, anaerobic compost pile than waterlogging. The ideal water content for rapid composting is about 50–60 percent by weight, but knowing that isn’t very helpful, is it? In practice, this is the water content of a well-wrung sponge. How does this prescription square with the water content of typical compost materials? “Not very well” is the answer.

Kitchen waste and grass cuttings are at least 80 percent water, so a pile made entirely from such materials would be too wet, which would contribute to a lack of oxygen. You could solve the problem by adding drier, woody waste, shredded or otherwise, but this would slow things down too much. The solution once more is paper and cardboard, which not only lowers the average water content of the pile, but also soaks up the liquid that is released as the softer materials start to decompose.

Why compost?

There are plenty of very good reasons for gardeners to make compost, but above all, it spares the environment the damage caused by
burying or burning waste, reduces the need to destroy natural habitats by excavating peat, and saves you money. don’t dump it, Recycle it US household garbage adds up to more than 200 million tons a year, or roughly 5 pounds (2 kg) per person per day, of which about a quarter is recycled. Only about ten percent of British household waste is recycled, which puts the UK near the bottom of the European league. Some countries, like Germany and Denmark, do much better, although a few are even worse. Most waste is incinerated or ends up in landfill, yet about half of all household waste could be composted. At the same time, every year gardeners around the world buy millions of tons of growing media, soil conditioners, and mulching materials, much of it based on peat. A high proportion of this could be replaced, free of charge, if gardeners started recycling what they now simply throw away. Incinerated waste is returned immediately to the air as carbon dioxide (CO2) and other gases, causing air pollution and contributing to global warming. Organic matter in landfill also slowly decays, but the main product is methane, an even worse greenhouse gas than CO2, and 25 percent of US methane emissions come from biodegradable waste in landfill sites. The soil is also the safest place for waste organic matter. Once returned to temperate soils as compost, some organic matter stays there, often for a long time. More widespread use of compost by farmers and gardeners could make a small but significant contribution to the commitments made in the Kyoto Protocol of 1997 to reduce CO2 emissions.

Treat your Soil

It’s hard to believe just how many benefits compost provides for soil. Even when spread on the surface as a mulch, and long before it actually enters the soil, compost elps to suppress weeds, retains soil moisture in dry conditions, and protects soil from the damaging effects of wind and heavy rain. But it’s when organic matter gets into the soil that it really starts to work its magic. Soil structure depends almost entirely on organic matter. In healthy soil, the organic humus and inert mineral particles are stuck together in tiny crumbs a fraction of an inch across. These crumbs are held together by fine fungal strands, or hyphae, and by organic glues produced by trillions of bacteria.

Leaves that are low in nitrogen and calcium, like those of larch and this pine, make truly awful compost.

materials containing calcium are great for the pile. Acidic soil can easily be corrected by adding garden lime (ground limestone), but there is no simple way of making an alkaline soil more acidic. If your compost pile is acidic because of poor aeration, it’s far better to treat the cause rather than attempt to treat the symptoms by adding lime. However, although most green waste contains plenty of calcium, some compost materials are naturally low in calcium. For example, fall leaves of oak and hornbeam are relatively rich—for tree leaves—in nitrogen, yet do not make good compost, which makes sense when you discover that both are low in calcium. Woody waste such as hedge prunings, especially of conifers, is also short of calcium, so here there is a case for adding lime to help it break down. The correlation isn’t perfect, but materials that are high in calcium also tend to be high in nitrogen, and no low-calcium materials contain more than moderate levels of nitrogen.

High in calcium Annual and perennial weeds; brassica leaves and stalks; kitchen vegetable waste; leaves of ash, cherry, elm, hawthorn, linden, maple, and rose; seaweed.

Low in calcium Bark, bracken, and ferns generally; conifer needles; hay and straw; leaves of beech, birch,

hornbeam, and oak; moss; wood.

What every gardener wants: compost.

Somewhere in this process—between the large amount of original material and the tiny fraction that is left as humus— lies The entire composting process can be seen on any woodland floor. On the surface are freshly fallen, unaltered leaves. Dig down a little way and the leaves become more fragmented and much less distinct. Eventually, you will come to a dark, crumbly material in which the original leaves are quite unrecognizable. This is usually called leafmold, but it’s just a special variety of compost, made only from tree leaves rather than the usual mixture of materials.

What is compost?

When animals and plants die, they decompose surprisingly quickly. The body of an adult human, if exposed to the elements, is reduced to a mere skeleton in about three weeks. The bones last longer, but not a great deal. Shakespeare was right when his gravedigger in Hamlet (Act V, Scene I) estimated there was not much left of a cadaver after eight or nine years. Even huge trees go the same way, and about as quickly. The end product of this composting process is a remarkably resistant and complex organic substance called humus, which is largely responsible for the brown color of the majority of soils in temperate regions. Humus is a mixture of the highly altered remains of the original organic matter—whether from plants or animals—that arrives at the soil surface, as well as new compounds made by bacteria and fungi. But only a small fraction of the original material is destined to become humus. Most simply disappears, turned back into the carbon dioxide (CO2), water, and mineral salts from which it was first made.