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How to Make Good Compost

A practical guide to help you reduce the weight of your dustbin and enrich the quality of your garden soil. Join in the campaign to make Portsmouth even greener.

A SUITABLE CONTAINER

There are several commercially produced containers available but these tend to be expensive. If you require the compost bin to be clean and tidy then one of these will be very suitable.
Ensure you choose one that is strong and will fit into the area you have available. There are types that enable you to shovel out the matured compost from a hatch at the base, look carefully to ensure the whole bin is not capable of collapsing when using this facility.

DO YOU HAVE TO USE A CONTAINER?

No, but it does give you better control and keeps the garden nice and tidy.

WOULD YOU PREFER A TRADITIONAL HEAP?

A compost heap is best covered at all times of the year. A piece of carpet is quite useful to cover a heap and also helps it stay tidy
After each 100mm (4") layer of compost, add a 50mm (2") layer of soil. This will keep the compost moist and tidy.

WHAT CAN BE COMPOSTED?

If we were to look seriously at what we throw away in the refuse bin, it would take a shorter time to describe what should not be composted!
All vegetable peelings, vacuum cleaner contents, pet hair, old woollens, paper which is loosely crumpled into single sheets and dampened, torn up packets, tea bags and lots of other material which you consider will rot.

THINGS TO AVOID

Never include plastics, metals, man-made fabrics or cooked food, these all encourage problems and in particular rats and mice.

WHAT ABOUT WEEDS?

Try to avoid including weeds that are about to flower, if you include weeds which will seed, you will not be pleased with the results. Difficult weeds are best tied up in black Polythene bags and left to rot. After a few months they may be added to the compost heap but if weeds are included, always dig the compost in deeply otherwise you will not thank us for the millions of weeds.

HELPING THE COMPOST TO ROT

After a short while, bacteria form naturally from the materials used in the compost but it is wise to add an activator to help increase the bacterial action.

ACTIVATORS

If you would like to be as environmentally friendly as possible, use one of these or use them alternately to judge for yourself which you consider to be the best :

• a layer of stinging nettle leaves simply sprinkled on top
• 1kg (2 lbs) of Comfrey leaves left in 1 litre (2 pints) of water for 10 days and then watered over the top of the compost, simply pour over the mucky liquid, solids included
• 50g (2ozs) of Garrota powder obtainable from a garden centre
• if you are really serious about protecting the environment then use 1 part urine in 7 parts water and sprinkle this over the compost after adding a 75mm (3") layer of material
• Sulphate of Ammonia or Fish Blood and Bone Fertilisers sprinkled on at a rate of 50g (2 ozs) over the top of each 75mm (3") layer
• a layer of seaweed also acts as an excellent activator

HOW LONG DOES IT TAKE TO OBTAIN GOOD COMPOST?

In the summer, it usually takes about 12 weeks for materials to break down well. In winter there is reduced activity by the bacteria, but about 18 weeks is a good estimate.

IS IT WORTH ALL THE EFFORT?

YES. There is an old saying - always put back into the soil everything you take out. On top of which there will be very little to put into your refuse bin and your garden will come up smelling of roses.

WHAT CAN I DO IF I PRODUCE TOO MUCH COMPOST?

This is unusual because good compost rots into humus, which is less than 5% of the material you decided to compost
If there is a glut, then dig partially rotted material into the garden in a trench and the natural soil bacteria will break it down quite quickly.

WHAT ABOUT MILLIONS OF LEAVES?

Bag them up into black polythene bags, add 1 part urine to 7 parts water and sprinkle this over each 100mm (4") layer of leaves. Tie the bags tightly and leave for about a year to rot. The resulting leaf mould is worth its weight in gold.

WHAT ABOUT HEDGE CLIPPINGS AND WOODY MATERIAL?

Include both, ensuring the materials are broken into small pieces and mixed with other waste. A shredder will do this very rapidly. Sharp secateurs can be used for small amounts of woody material.
You might consider using evergreen conifer and evergreen hedge clippings as mulch over the top of soil in shrub borders. It is an excellent weed depressant and best used as mulch.

WHAT ABOUT PILES OF MOWINGS?

Add mowings to other material, even lightly screwed up paper so that it isn't included as a thick thatch. The additional air helps the grass to rot quite well, the grass heats up quickly and will help kill off weed seeds.

WHAT ABOUT SMELLS?

What smells? Keep the compost covered and there is no smell.

WHAT ABOUT WOODLICE AND PESTS?

Look at things differently, if they are in the compost, at least you know where they are!