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Composting - Make your own compost

Garden and domestic refuse can be used to make excellent compost. The compost bin used is important, both to tidiness and to holding the heat, making the difference between a compost heap and a rubbish heap.

Composting Requirements

SHREDDED ORGANIC WASTES. Shredding, chopping or even bruising organic materials hastens decay. One way to shred leaves is to mow the lawn before raking, collecting the shredded leaves in the mower bag. It takes at least 34 cubic feet of shredded material to form a compost pile.
GOOD LOCATION. The compost pile should be located in a warm area and protected from overexposure to wind and too much direct sunlight. While heat and air facilitate composting, overexposure dries the materials. The location should not offend neighbours.
NITROGEN. Nitrogen accelerates composting. Good sources include fresh grass clippings, manure, blood meal and nitrogenous fertilizer. Lime should be used sparingly if at all. It enhances decomposition, but too much causes nitrogen loss, and it usually isn't necessary unless the pile contains large amounts of pine and spruce needles or fruit wastes.
AIR. The compost pile and its enclosure should be well ventilated. Some decay will occur without oxygen, but the process is slow and causes doors.
WATER. Materials in the compost pile should be kept as moist as a squeezed sponge. Too little or too much water retards decomposition. Over watering causes doors and loss of nutrients.
 

Building the Heap

Choose a site in a sheltered place, which can be in a dry shade under a tree where nothing much will grow, but in this position the heap will need watering in dry weather. Level off the ground and flatten it with a spade. Cover the base of the compost heap with tough and stemmy rubbish, such as hedge clippings or tall tough weeds. This prevents finer materials from blocking the air channels. Then pile on the first 8 inch thick layer of weeds, lawn-mowings and garden waste, with kitchen waste in the middle.

Scatter enough dried poultry manure or other available manure to cover the surface. Add another 8 inch layer of rubbish, whiten this with lime, pile on a third layer and then add manure or ‘activator’ again. Repeat this sequence until the container is filled. This is rarely possible in a day as most heaps take weeks to build, adding more layers as they sink and decay until the heap is cold and the worms move in.

Other signs that the compost is ready are a faint earthy odour (the only smell), dark brown or black colour and a crumbly texture like well-rotted farmyard manure. Used like manure (though it is richer than potash) it can be dug in before sowing root crops without making them coarse and forky, and with lime, a bucketful a square yard is a fair dressing. Autumn heaps are ready to dig in by Spring and summer heaps are mature ready for Autumn digging, so with enough material a container can be filled and emptied 3 times a year.

There are many propriety activators which do not need lime layers. Though layers of soil are often recommended where weeds have soil on the roots, it is unnecessary. Compost producing crops of weed seedlings can result when not enough soil off has been shaken off.


What can go in the Compost Heap

Autumn leaves
Store some dry leaves to mix with grass mowings and other soft green stuff. Make large quantities into leaf mould - stuff wet leaves into black plastic sacks (loosely tied), or a wire mesh container. Use after a year or two. Mow leaves on a lawn to chop and collect them up. Grass mowings
Mix well with tougher items to avoid a slimy mess. Leave on the lawn whenever possible - they will soon disappear and feed the grass; this will not cause 'thatch'. Can also be mixed into a leaf mould heap, or used as a soil mulch.

Diseased plants
Persistent diseases, such as white rot and clubroot, are best avoided. A hot heap, turned several times, should deal with everything else.

Diseases that don't need living plants to survive - grey mould, mildews, wilts - may survive in a slow, cool heap. But heat is not the only factor that will kill diseases - the intense microbial activity will also help to dispose of them.

Perennial weeds
Some perennial weeds will be killed in a hot heap; avoid really persistent horrors such as celandine, bulbous buttercup, ground elder and bindweed. Don't burn or dump these weeds - they are rich in plant foods. Mix with grass mowings in a plastic sack. Tie it up and leave for a few months until the weeds are no longer recognisable, then add to the compost heap.

Weed seeds
Weed seeds may survive a cool heap, but should be killed in a hot one. If your compost tends to grow weeds, dig it in rather than spreading it on the soil surface.

Hedge clippings and prunings
Chop or shred tough prunings and clippings from evergreen hedges before adding to a mixed compost heap. Compost large quantities separately; even unshredded they will rot eventually. Mix with grass or other activating material; water well. Tread down the heap, then cover. In anything from a few months to years you will have a coarse mulch which can be used on perennial beds.

Animal manures
Strawy horse and cattle manure composts well. Keep a sack on hand to bulk up other ingredients. Manure mixed with wood shavings should be left to rot until the shavings are no longer visible. If it is dry, water well and mix with grass mowings, poultry manure or other activating material. When rotted use as a surface mulch. Wood shavings incorporated into the soil can lock up soil nitrogen, making it unavailable for plants for a year or more.

Small pets, like hamsters, don't produce many droppings but you can still use their waste as a strawy addition to the compost heap. Guinea pigs are marvellous - they love eating weeds and convert them quickly to prime compost material!

Paper products
Newspaper can be added to a compost heap, but in any quantity it should go for recycling into more paper. Cardboard, paper towels and other paper items can be crumpled up and composted. They are particularly useful where kitchen scraps make up a high proportion of the compost ingredients. Avoid glossy paper and colour print.

Sawdust and wood shavings
Very slow to decay. Add in small quantities; balance with quick-to-rot activating materials. See also 'Animal manures' above. Do not use if treated with wood preservatives.  

What to Leave Out

Metal of any kind including bottle tops, broken china, newspaper and cardboard in bulk, polythene and plastics. Tree prunings, pine needles, sawdust wood shavings thick branches and clippings will all decay in time

Kitchen Wastes in Winter

If in winter there are too few weeds to cover the kitchen wastes, bury them in a heap or dig a trench a spade wide and a foot deep. Cover it with soil. When the trench is full, scatter Lime generously on the surface and leave to sink. Potato peelings should not go into trenches – odd eyes will grow and crowd the peas unless the winter is very cold.


Troubleshooting Composting Problems

Problems Possible Causes Solution
Damp and warm only in the middle of the pile. Pile could be too small, or cold weather might have slowed composting
If you are only composting in piles, make sure your pile is at least 3 feet high and 3 feet wide. With a bin, the pile doesn't need to be so large.
Nothing is happening. Pile doesn't seem to be heating up at all. 1. Not enough nitrogen
2. Not enough oxygen
3. Not enough moisture
4. Cold weather?
5. Compost is finished.
1. Make sure you have enough nitrogen rich sources like manure, grass clippings or food scraps.
2. Mix up the pile so it can breathe.
3. Mix up the pile and water it with the hose so that there is some moisture in the pile. A completely dry pile doesn't compost.
4. Wait for spring, cover the pile, or use a bin.
Matted leaves or grass clippings aren't decomposing. Poor aeration, or lack of moisture. Avoid thick layers of just one material. Too much of something like leaves, paper or grass clippings don't break down well. Break up the layers and mix up the pile so that there is a good mix of materials. Shred any big material that isn't breaking down well.
Stinks like rancid butter, vinegar or rotten eggs. Not enough oxygen, or the pile is too wet, or compacted.
Mix up the pile so that it gets some aeration and can breathe. Add course dry materials like straw, hay or leaves to soak up excess moisture. If smell is too bad, add dry materials on top and wait until it dries out a bit before you mix the pile.
Odor like ammonia. Not enough carbon. Add brown materials like leaves, straw, hay, shredded newspaper, etc.
Attracts rodents, flies, or other animals. Inappropriate materials (like meat, oil, bones), or the food-like material is too close to the surface of the pile. Bury kitchen scraps near the center of the pile. Don't add inappropriate materials to compost. Switch to a rodent-proof closed bin.
Attracts insects, millipedes, slugs, etc. This is normal composting, and part of the natural process. Not a problem.
Fire ant problems.
Pile could be too dry, not hot enough, or has kitchen scraps too close to the surface.
Make sure your pile has a good mix of materials to heat up, and keep it moist enough.