Composting is a boon, once you get started. Jane Powersshows how
One of my favourite sights in our garden is that of steam rising from the compost heap. It means I've got it right: the perfect mixture of "greens" (materials high in nitrogen, such as grass clippings and soft weeds) and "browns" (carbon-rich, dried plant matter, and the odd bit of paper or cardboard), combined with enough moisture and air to set it magically cooking. When steam is rising it means that the heap has been colonised by billions of thermophilic bacteria, a bunch of do-good organisms who live at temperatures of between 45 and 70 degrees Centigrade. The heat and the enzymes generated by these bacteria (of the genus Thermus) help to break down the cellulose in the material, and also to destroy pathogens and weed seeds.
If you have room for a sizeable composting operation, it's not too hard to achieve a satisfactorily sweltering heap. The textbook way of doing it is to stockpile your compostables until you have enough to build a heap all in one go. Then you mix them together in the right proportions of "green" and "brown" (around two or three parts of the first to one part of the second), water the heap or bin, cover it, and off it goes. In a couple of days it will be so hot you won't be able to keep your hand in it. When the heat lessens, use a garden fork to turn the heap into an adjacent bin or pile, and the newly added air will promote another blast of torrid activity. Turn it again and it hots up again, and so on, and so on.
That's the theory. The reality is usually different, as few households produce such model amounts of compost ingredients in such conveniently timed doses. Carbon-heavy matter (the crunchy, dry stuff) doesn't mind waiting around, but nitrogen-rich material (grass and other soft green growth, poultry manure, seaweed, kitchen waste) doesn't hang about quietly. It begins to decay immediately, and, if there is not enough air in the process, it starts to pong and produce methane - a rather serious greenhouse gas.
It is more expedient to build your compost pile in layers (rather than in one fell swoop) as soon as green matter becomes available - after mowing the lawn, or doing a major weeding session, for example. If you can rustle up enough stuff to add a 40cm layer (although deeper is better) to your heap each time, there will usually be enough volume to kick-start the heat-loving bacteria. Don't worry if you haven't been able to gather enough brown/carbon material from the garden, you can supplement with torn-up newspaper, corrugated cardboard, straw or used paper towels.
Okay, now let's be honest people: if you are able to carry out your composting as I've just described then you are a perfect person, with admirable management skills, and plenty of time to devote to the enjoyable business of turning waste into humus. For most of us, most of the time, it's a matter of flinging the stuff into a pile or bin, and letting it get on with the decomposition process at its own pace - without the help of those impressively energetic thermophilic bacteria.
But, there's nothing wrong with this approach, because Mother Nature is on our side. Her mission is to continually break down erstwhile living things into soil: otherwise the earth's surface would be piled sky high with perfectly-preserved dead plants, insects, animals and people. Therefore, any heap of anything that once grew will eventually rot down into usable compost. Bacteria (mesophilic kinds, which are active at lower temperatures) start the decomposition process; fungi and minute organisms, called protozoa and rotifers, move in next. Larger creatures, such as woodlice, millipedes, slugs (don't worry, these ones like dead material, not live plants) and brandling worms complete the operation. When you see these last - which are redder and thinner than earthworms - you know your compost is ready for use.
If you remember just one thing, it's this: don't add too much "green" or "brown" at any one time. Pure grass clippings will turn into a suffocating sludge, while dry twiggy material will remain just that. Mix the two together and the lovely, crumbly humus will metamorphose more quickly and with less trouble.
You'll have to wait up to a year for your first home-made compost, but then you can use it for a hundred different things. Add it to light soil to bulk it up, and to heavy soil to lighten it. Mix it with commercial potting compost to increase nutriments and to cut on cost. Add it to planting holes when putting in new shrubs, perennials or climbers. Layer it on vegetable beds and flower borders, and brush it over the lawn, and the worms will dig it in for you. Mix it with water, and use it as a liquid feed for your plants.
Compost is not just good for your garden, it's good for you too. Making it is an exhilarating process, a little like putting your hand to the great wheel of nature and making it spin faster. It's fun to be a rotter.
Further reading:Compost by Ken Thompson (Dorling Kindersley £12.99)
DO COMPOST
All healthy plant material, including weeds (preferably without seeds), grass clippings, shredded prunings and hedge clippings, autumn leaves, uncooked vegetable waste, tea leaves, coffee grounds, nut shells, eggshells, farmyard and poultry manure, litter from herbivore pets such as rabbits and guinea pigs, seaweed (but don't cut it off rocks), small amounts of non-glossy newspaper and cardboard, kitchen towels, toilet roll cores, hair, feathers, contents of vacuum cleaner bags, wood ash (in moderation).
DON'T COMPOST
Seriously diseased plants, plant material that has been treated with chemicals, thick woody stuff, roots of perennial weeds (unless you've left them to dry out first), meat and dairy products, oil, cooked food, cat litter and dog faeces, coal ashes. A word about peat ashes: I've advised against composting peat ashes in the past, but I've since read that they may be successfully used in compost heaps. If you do add them, mix them in well (or they'll make an airtight, inert layer), and keep the quantity small.