HOW TO MAKE A COMPOST HEAP
From 'Manure from Garden Rubbish' - Dig for Victory Leaflet
By means of a compost heap, demanding neither much time nor labour, and little
or no expense, all the vegetable waste of the garden can be turned into valuable manure. Leaves, grass cuttings,
sods, lawn mowings, pea or bean or potato haulms, outer leaves or tops of vegetables,
hedge clippings, weeds and faded flowers; in short, any plant refuse, green or otherwise,
can be used for manurial purposes. Such a conversion of waste to good use, if widely
adopted, can make a considerable contribution to the national effort for increased food
The process known as composting is based on the fact that if vegetable
matter, soil, water and air are brought together and provided with a " starter," which may
be animal manure or a ehemical, a fermentation or digestion takes place. Lime (especially
slaked lime or chalk) is necessary to neutralize the acids which are formed. This
action converts the materials in humus, a substance essential for maintaining the fertility
of all soils.
Kitchen refuse, if it cannot be fed to pigs or livestock, should
be well mixed with the other material and added to the heap.
Autumn leaves, on account of their dryness, tend to decompose
slowly, and should be mixed with sappy material or even dealt with in a separate heap.
Decomposition of very fibrous matter, such as the stems of some herbaceous plants, cabbage
stumps or potato haulms, will be hastened if it is chopped into short lengths and broken up.
How to Make a Compost Heap
The heap should be made in the shape shown in the sketch above, 4-7 ft.
wide, 3-5 ft. high and of any convenient length according to the amount of material
likely to be available; The turf and soil are removed from the site (preferably a spot
shaded from the full heat of the sun) to a depth of one foot and retained on one side.
Layers of materials are then put in as follows:-
First. A layer of vegetable refuse (the more mixed it is the better) about
4-6 in. thick.
Should it be dry and stemmy, moisten it (not more) and trample it well
- the more broken it is, the better. If green and sappy, lay it loosely.
Second. A layer of animal manure (from horse, cow, pig or small livestock
- best of all, mixed) 1/2-l in. thick;
or a sprinkling of one of the proprietary chemicals sold for this purpose by most
If animal manure has been used, a sprinkling of lime should be given
after each 4-6 in. layer of refuse, but it is best not to apply the lime directly on the
animal manure. A layer of refuse or soil should he left between the lime and the animal
If one of the proprietary compost makers is used, this will probably
contain sufficient lime.
Wood ashes or bonfire ashes may be used in place of lime, and any kind
of liquid manure loay take the place of animal manure.
Third. A layer of soil 1/2-l in. thick. In summer or with dry materials,
more should be used; in winter or with sappy stuff, less is necessary. If the soil is
loose in texture, it should be more generously applied than soil of a stiff or sticky
nature. If available, it will .be a great help if a little old oompost from an earlier
heap is mixed with the soil.
These three basic layers should he repeated until the full height is
reached, and the whole heap should then be eovered with a coating of soil 1/2-l in. thick.
No other chemicals are needed, but wood or bonfire ashes, and any kind ol liquid manure
may be added during the building of the heap.
In many gardens, sufficient material will probably not he available to make a complete
heap at one operation, and the heap may be built gradually; but after about two veeks in
summer, or six weeks in winter, it should he finished off, even if the prescribed height
has not been reached, and a new one started.
Turning the Heap
In a few days according to the material and the weather conditions, the
heap should generate heat; or at least become warm. If it does not, no harm is done, but
it will he longer before the material is ready for use. A heap which has become very hot
(hotter in the middle than can be borne by the bare hand) may be turned over after 3-6
veeks, when it has begun to cool down. A cool heap should be left 6-12 weeks before
turning over. Turning over should he done from one end, mixing the layers, and the
original outside of the heap should be thrown inside.
After a further period, which may vary from 3 weeks to 6 months, the
whole heap should be uniformly dark in colour, with a pleasant earthy smell, and all the
material completely rotted. It is then ready for use. A second or third turning will
accelerate the completion of the process, but is not normally necessary.
If the composting is properly done, perennial roots, such as couch
grass, and the seeds of annual weeds will be destroyed by the combination of heat,
moisture and active fermentation.
A Valuable Manure
The amount of nitrogen in well-made compost from garden waste may equal
that in farmyard manure, and the potash and phosphate contents may be even higher. It is
a valuable manure for all crops, and should be buried not more than 3-4 in.deep. Lightly
hoed in, it is an excellent mulch or top-dressing.
Materials not to be used
These include cinders, paper (both of which should in any event not be
classed as waste), coal ashes, very thick woody stems or cuttings, sawdust, or any
material tainted with oil, creosote, tar or any poisononous or preservative chemical.
The Garden Bonfire
This should be restricted to the smallest limits and confined
to woody material, old pea sticks, diseased material and the thickest underground parts
of docks, etc. All other vegetation should find its.way back to the soil.
The ashes from a bonfire should not be left out for the rain and dew to
wash away the very soluble form of potash coutained in them. They should be dug in
immediately they are cold, incorporated in the compost heap, or bagged and stored in a
The bonfire should he started in good time for it to be out before the black-out hour.