Agrodok 8

The preparation and use ofcompostMadeleine InckelPeter de Smet
Tim Tersmette
Tom Veldkamp

© Agromisa Foundation, Wageningen, 2005.
All rights reserved. No part of this book may be reproduced in any form, by print, photocopy,
microfilm or any other means, without written permission from the publisher.
First edition: 1980
Fifth revised edition: 1999
Seventh edition: 2005
Authors: Madeleine Inckel, Peter de Smet, Tim Tersmette, Tom Veldkamp
Translation: Mrs. E.W.M. Verheij
Printed by: Digigrafi, Wageningen, The Netherlands
Third revision by: Mira Louis and Marg Leijdens
ISBN: 90-8573-006-6
NUGI: 835

Foreword
Foreword to the third revised edition
This booklet has been compiled to give information about how compost can be applied in the tropics and subtropics. It gives a simple description of the processes taking place in the soil and during composting. Practical suggestions are given for constructing a compost heap. A
few selected compost methods and applications are given and a literature list has been added for supplementary information.

The reader is advised to first read through the whole booklet to get a
general impression before looking for specific information. We welcome, with interest, any remarks, additions or queries about this booklet or related matters.
The Authors
Wageningen, May 1990.
Foreword to the fourth revised edition
We have made some minor alterations in this third revised edition.
Hopefully this Agrodok will continue to be a help to produce yourown compost.

The publisher
Wageningen, October 1994.
Foreword to the fifth revised edition
We thank Mira Louis for preparing materials for this 5th revision.
KIOF, The Kenyan Institute for Organic Farming in Nairobi, and theHenry Doubleday Research Association (HDRA) in Coventry, UK,both gave us valuable information to improve this Agrodok. We arevery grateful to them. Their addresses are given in the back of thisbook. We hope that many people will make use of the information
given.

Marg Leijdens, Coordinator Agrodok Publications
Wageningen, 1999.

Foreword

3

Contents
1

Reasons for composting

6

2
2.1
2.2

Fertilizing: the role of organic matter and compost
Organic matter and soil processes
Compost

8
8
9

3
3.1
3.2
3.3

The composting process
Heating phase
Cooling down phase
Maturation phase

11
12
13
13

4
4.1
4.2
4.3
4.4
4.5
4.6

The practice of composting
Organic material
Micro-organisms
Air
Moisture
Site of the compost heap
Size and setting up of the heap

14
14
16
16
17
17
19

5
5.1
5.2
5.3
5.4
5.5
5.6
5.7

Methods to make compost
Indore method
Bangalore method
Heating process or block method
Pit composting
Trench composting
Basket composting
Boma composting

22
22
24
25
27
28
29
30

6
6.1
6.2
6.3
6.4

Composting specific materials
Composting water plants
Composting seaweed
Composting coffee pulp
Composting domestic waste

33
33
34
35
36

4

The preparation and use of compost

6.5

Composting human waste or sewage

39

7
7.1
7.2
7.3
7.4

Putting compost to use
Fertilizing
Nursery soil, potting soil, planting trees
Erosion prevention and erosion control
Compost for fish feed

40
40
42
43
43

8
8.1

Liquid manure and plant teas
How to make liquid manure and plant teas

47
47

9
9.1
9.2
9.3

BokashiThe organic materials
Preparation of bokashi
Applying bokashi

50
51
53
56

10 Your own organic fertilizer
10.1 Advantages and disadvantages
10.2 Whether or not to start preparing organic fertilizers
10.3 Practical questions as a guideline for starting

57
57
58
59

Appendix 1: Composition of organic materials

60

Further reading

62

Useful addresses

64

Contents5

1

Reasons for composting

Compost is an organic fertilizer that can be made on the farm at very
low cost. The most important input is the farmer’s labour. Compost isdecomposed organic matter, such as crop residues and/or animal manure. Most of these ingredients can be easily found around the farm.
Agromisa’s Question and Answer Service frequently receives questions from farmers who face a problem with a decreasing fertility of
their soils. Due to soil fertility problems, crop returns often decrease
and the crops are more susceptible to pests and diseases because they
are in bad condition.
In order to increase soil fertility in the short run, nutrients have to be
added to the soil. This is often done by applying chemical fertilizers.
Chemical fertilizers, however, are expensive to purchase and for mostsmall-scale farmers this is a problem. Preparation and use of compost
can be a solution to that problem.
To really improve soil fertility in the long term, it is necessary to improve the soil structure and to increase the organic matter content of
the soil. Compost is a good fertilizer because it contains nutrients aswell as organic matter. The role of organic matter is explained in moredetail in Chapter 2.
Using compost as the only means to maintain soil fertility is possible,
but in that case you need a very large quantity of compost. We advise
you to apply several practices at the same time in order to maintain thesoil fertility in the long term.
Some of these methods to improve soil fertility are:
? Crop husbandry methods, such as: mulching, green manure, agroforestry and improved fallow.
? Applying organic manures such as: compost, liquid manure andanimal manure.

6

The preparation and use of compost

If animal manure is applied it should have matured for some time,other-wise it might damage the plants. Composting animal manure
makes it a better fertilizer.
These methods to improve soil fertlility and others are described extensively in Agrodok no. 2: ‘Soil fertility management’ and Agrodok
no. 16: ‘Agroforestry’.
Contents of this Agrodok
This Agrodok concentrates on the preparation and use of compost.
Chapter 8 gives a recipe of making liquid manure and plant teas.
These are organic fertilizers that are easily made to supply plants
quickly with nutrients. Bokashi is another type of organic fertilizer,
prepared by fermenting organic matter. In Chapter 9 it is explained indetail.

This Agrodok has been written for people who work with small scale
farmers in developing countries and for anybody with an interest incomposting and organic fertilizers.

Figure 1: Turning compost (Source: KIOF)

Reasons for composting7

2

Fertilizing: the role of organic
matter and compost

The presence of organic matter in the soil is fundamental in maintaining the soil fertility and decreasing nutrient losses. Compost is an organic fertilizer; it adds organic matter and nutrients to the soil.
In order to quickly supply a crop with the required nutrients, a chemical fertilizer may be needed. In contrast to organic fertilizers, chemicalfertilizers help the plants immediately; organic manures first have to
be broken down into nutrients (by soil-organisms) before they can beutilized by the plants.
However, chemical fertilizers are used up by the end of the season,
whereas organic matter continues to enhance soil fertility, soil structure and water storage capacity.
Moreover, the presence of organic material ensures that the chemicalfertilizer is more efficiently utilized by the crop. Organic matter retains plant nutrients and thus prevents the fertilizer from being washedaway. It is in fact a waste of money to apply chemical fertilizer on asoil that is poor in organic matter, if it is not done in combination withmeasures to increase the level of organic matter in the soil.

2.1

Organic matter and soil processes

Organic matter in the soil consists of fresh organic matter and humus.
Fresh organic matter can be (dead) plant material, animal droppings,
dead animals etc. The fresh organic matter is transformed into fineorganic matter and humus by soil organisms.
Humus gives the soil a dark color and retains nutrients and water. It
cannot easily be decomposed further. The fine organic matter, andhumus in particular, have the following properties:

8

The preparation and use of compost

? it improves the soil structure.
? it improves the resistance of the soil against the erosive action ofrain and wind.
? it retains water and releases it slowly, so that water is available tothe plants (water storage capacity) over a longer period.
? it retains nutrients and releases them to the plants slowly over alonger period.
? it contains the main nutrients: nitrogen (N), phosphorus (P) and potassium (K), which become available to the plants after decomposition.

Figure 2: A few soil organisms, some can hardly be seen by the
naked eye

The micro-organisms are mainly responsible for further breaking
down part of the humus into carbon dioxide, water and nutrients forthe plants. This process is called mineralization: nutrients are released
and can be taken up directly by plant roots.
The rate of humus production and mineralization in the soil depends
on a number of factors. In a hot climate the micro-organisms are more
active and the organic materials will break down more rapidly than ina cold climate. Also the acidity of the soil, the composition of the organic matter, the humidity and the availability of oxygen strongly influence the rate of decomposition.

2.2

CompostThe natural decomposition process in the soil can be regulated andspeeded up by man. Organic material is collected, and preferably

Fertilizing: the role of organic matter and compost

9stacked in a heap. In the heap the decomposition process is more intensive and the conditions more favourable, because the heap is madeup almost entirely of organic matter. The end product is strongly decayed organic matter with humus and nutrients. This is known ascompost. Compost is used as an organic fertilizer that can be added tothe soil.
Fertilizing with compost means, apart from fertilizing the plants, also
making use of the good properties of organic material as mentioned in
the section above.
Adding compost to sandy soils increases the water retention capacity.
This means that water remains longer in the soil and thus remains
available to plants for a longer time in periods of drought.
All non-toxic, organic materials can be used for making compost. Superfluous and/or waste material are often applied and in this way canbe made use of again. Finally, make sure that the materials used forcomposting could not be better used for other purposes, such as cattle
feed.

10

The preparation and use of compost

3

The composting process

As described in the section on organic matter in soil processes, thecomposting process happens due to the activity of micro-organisms(bacteria) and other larger organisms like worms and insects. These
need certain conditions to live. These include moisture and air.
To make the best possible compost, the micro-organisms must be able
to work optimally. This can be achieved if the following four factors
are combined to the best advantage:? type of organic material? air? moisture? temperature
The acidity (pH) is also considered by some to be an important factor.
Acidity depends on the air and moisture flow. A compost heap that isproperly composed will seldom get too acid.
The composting process will be optimal when:? various materials of different decomposition rates are combined;? the different materials are well mixed;? the size of the heap varies from 1 x 1 meters to 3 x 3 meters. This
makes it possible for the temperature to stay constant within theheap.
A good composting process passes through 3 consecutive stages, these
are as follows:? a heating phase (fermentation)? a cooling down phase? a maturation phase
It is not easy to draw the line between these stages. The process takes
place very gradually and with the help of continuously changing micro-organisms the organic material is converted into compost.

The composting process

11

3.1

Heating phase

During the first stage of composting, the compost heap starts to heatup considerably. This effect is known as fermentation and is the resultof the breaking down of the complex and tough fibrous material of theorganic matter. This fermentation process (decomposition) is strongest
in the centre of the heap.
To get the fermentation going quickly and effectively, a number offactors are important. In the first place the compost heap should bemade of all sorts of organic materials. Secondly, the right microorganisms have to be present. Thirdly, it is very important that there isadequate oxygen and water. If these three conditions are met, heat is
generated quickly. In the next chapter we explain how to meet these
conditions when putting compost making into practice.
During fermentation the micro-organisms multiply and change at a
rapid rate, which adds to the heating up process. In this way, a selfaccelerated process is started. The fermentation stage usually begins
after 4-5 days and may take 1-2 weeks.
Maximum fermentation takes place at a temperature of 60-70 oC in thecompost heap. If the temperature is too high, the necessary microorganisms may die and decomposition comes to a halt.
Due to its temperature, fermentation also has a hygienic effect. In theorganic material, many pathogenic germs that are a threat to man,animal and plant, are destroyed. It is often suggested that fermentation
kills weed seeds and roots too. However, in practice, this is quite disappointing. Many weed seeds are not destroyed in a normal compost
heap, because the temperature is not sufficiently high. In some cases,
the germinating power of weed seeds has even been known to increase.
Temperature test
A simple way to see if the fermentation process has started is as follows: put a stick in the centre of the heap about 5 days after completing the compost heap or after the final turning over. Leave it there forabout 5 to 10 minutes.
12

The preparation and use of compost

After taking it out, feel it immediately. It should be considerably
warmer (60 - 70 oC) than body temperature. If not, then this is an indication that something is wrong, perhaps the material used or aeration
is at fault.

3.2

Cooling down phase

The fermentation phase gradually changes into a cooling down phase.
Decomposition occurs without much generation of heat and the temperature drops slowly.
During this period new types of micro-organisms convert the organic
components into humus. The heap remains clammy and hot inside andthe temperature drops from 50oC to 30oC. By regulating the temperature, air and water supply, the process can be accelerated or slowed
down. How long this cooling down stage takes, depends on the type ofheap, the material, the attention given to it, the climate etc.
The cooling down period usually takes a few months, but in unfavourable conditions may require up to a year.

3.3

Maturation phase

In this end phase of decomposition, the temperature drops to soil temperature, depending on the climate, 15-25 oC.
Apart from the micro-organisms mentioned, the large soil fauna are
active at this stage too. In temperate regions, earthworms in particular,
feed on the strongly decomposed organic material, and in this way
contribute to decomposition.
In the tropical to semi arid regions, termites in particular play an important role, although these can also be very troublesome. This phasenever really comes to an end; the decomposition process can go on
infinitely at a slow rate. The compost is ready for use if it feels crumbly and looks like good brown/black organic soil.

The composting process

13

4

The practice of composting

In this chapter the important aspects of compost making are explained.
Attention must be given to the composition of the organic material andthe location of the heap. The measurements and the construction of theheap are described separately.
In the next chapter different specific methods of compost making are
given.

4.1

Organic material

In general, any type of organic material of plants and animals can beused. It is essential to mix old and tough materials, which are difficult
to decompose (crop residues, small twigs), with young and sappy materials, which are easily decomposable (fruit, vegetable skins, young
leaves).
This is because different types of organic matter contain different proportions of carbon (C) and nitrogen (N). The micro-organisms who
decompose the organic matter need both carbon and nitrogen to function well.
In general, young, living material that decomposes fast contains low
levels of carbon but high levels of nitrogen. Tough, dead material decomposes slowly and contains large amounts of carbon but low
amounts of nitrogen. Too little nitrogen-rich material means the composting process will be slow, too much of it will result in the heap becoming acid and smelly.
The ideal ratio of carbon and nitrogen for starting a compost pile is:
C : N ratio = 25-30 : 1
See appendix 1 for the composition of the most important materials
for composting.

14

The preparation and use of compost

Examples of nitrogen-rich materials are:Young leaves, all types of manures, fish meal, fish waste, urine, leguminous
plants.

Examples of carbon-rich materials are:Dry leaves, crop residues of maize, sugarcane, rice, etc., twigs, woodshavings, coffee pulp, carton, etc.

Table 1: Examples of the C:N ratio of some materials (Source:
KIOF).
Material
sawdustmaize stalks
straw
legumes and farm manure
manure with bedding material
hay from legumes
animal droppings

C:N Ratio
up to 400
50-150
50
20-30
20-25
15
15

Be careful not to use toxic materials. For example, plant parts sprayedwith chemical pesticides can have an adverse effect on the decomposition and the quality of the compost. Diseased material with rusts andviruses for example, should be kept to a minimum.
During fermentation many disease germs are not destroyed, so thedisease cycle continues as compost is added to the soil in the form of
manure.
A shortage of easily decomposable material is often the reason forslow conversion in the compost heap. The heap may even becomecompletely inactive. An indication of this is the fall in temperatureduring fermentation, after about two days.
A compost heap made up of young plant material (easy to decompose)gets going slowly and soon becomes too acid. An acid compost heap
begins to rot and smell. Decomposition takes place very slowly andthe quality of the compost deteriorates. The combination of young leaf
The practice of composting15

litter or manure (easy to decompose) with woody plant parts (difficult
to decompose) gives the best compost in the shortest time.
In appendix 1 you find a list, showing the composition of many typesof organic material which could be used for composting.

4.2

Micro-organisms

The composting process happens due to the activity of microorganisms and other larger organisms like worms and insects. See figure 2 in Section 2.1.
The first condition for composting is the presence of the compostingorganisms. Adding these organisms to the heap can be done by mixing
ready-made compost with the organic materials. If there is no compost
the soil can be added. Collect this soil preferably from a shady andhumid place, e.g. from below trees.
Soil that contains moisture, contains micro-organisms. Soil that has
been dried out by the sun, usually does not contain many living organisms anymore.

4.3

Air

The micro-organisms in the heap require oxygen to survive and to dotheir work converting the organic material. The carbon dioxide which
is produced by the micro-organisms as a result of their activity needs
to be blown out by a flow of air. If there is not enough air in the heap,
the useful micro-organisms will not survive. Other micro-organismsthat do not need oxygen will thrive and decomposition of the organic
material will slow down.
In order to get enough air in the heap do not put the compost heap
right up against a wall. When building up the heap put a layer of roughmaterial (twigs) at the bottom, so air can enter the heap. See also section 4.6 with the subsection on air channels.

16

The preparation and use of compost

4.4

Moisture

The micro-organisms need moisture to live and to spread through theheap. The activity of the organisms will slow down if the heap is toodry. But if the heap becomes too wet, then there will not be enough air
and the composting organisms will die. This will cause the heap toferment rather than compost. Judging the right amount of water requires a little experience.
Moisture test
The moisture level of a compost heap can be tested easily. Put a bundle of straw in the heap. If after 5 minutes it feels clammy, then the
moisture level is good; if still dry after 5 minutes, the moisture level is
too low.

A dry heap has to be sprinkled uniformly, using a watering can or aperforated tin. Water alone can be used or a mixture of urine and water
1:4. Urine enhances the growth of the micro-organisms.
Water droplets on the straw indicate that the heap is too wet and it
should be opened up straight away. The material can be spread out anddried in the sun. It can also be mixed with other dry material. Aftersome time the heap can be made up again. If it has become too wet byrain then it is better to cover it. Repeat the test in both cases after a
few days.

4.5

Site of the compost heap

Choosing a good place for a compost heap is important. Bear in mind
the following points:
ClimateIf weather conditions are mainly dry, the heap must be protectedagainst drying out. A shady place, out of the wind, is ideal. This could
be behind a building or behind a row of trees. Moisture in the heap
will then evaporate less quickly, yet there will be enough air.

The practice of composting17

A wind-free place also has the advantage that the material is not blown
away and the temperature fluctuates less. A water source near the heap
is convenient for sprinkling if too dry.
Under wet weather conditions the heap will have to be protectedagainst excess water. Choose a protected and well-drained place on ahigher part of the land. A compost heap under a shade tree (mango or
cashew, for instance) will usually be well protected against excessive
rainfall. Both types of weather conditions are likely to play an important role in determining a suitable place for making a compost heap.
Putting a simple roof above the place where the compost is made protects the heap against the sun and against the rain. The protection
against these climatic influences will improve the composting process.
Temperature and moisture level will stay more constant.

Figure 3: Simple roof above three compost heaps (Mira Louis)
Transport
The heap should be situated as close as possible to the source of organic material (for instance, the field or harvesting place). It should
also be near the place where the compost is to be used. This saves timeand labour in transport or organic material and compost.

18

The preparation and use of compost

Space around the heap
There should be enough space around the heap to enable the compost
to be turned over or examined. A space about 2 to 3 times that of theheap itself is the most practical.
Vermin
A compost heap should always be made outside and not too close toliving accommodation or stables. The heap is likely to attract a number of vermin, such as mice, rats, termites and other insects. Thesetransfer diseases to man and animal and attract more dangerous vermin, such as snakes.

4.6

Size and setting up of the heap

Size
The heap has to conform to a certain size; if too broad or too high,aeration is poor. A good basic size is 2 to 2.5 meters wide and 1.5 to 2
meters in height. The length depends on the quantity of organic material available, but it is better to make a shorter heap quickly than alonger heap slowly. It is strongly advised to start with a heap greaterthan 1 cubic meter, otherwise the temperature in the heap remains low
and decomposition is too slow and incomplete.

During the maturation phase the volume of the heap decreases; theheap sags in, as it were.
Setting up the heap
The compost heap can be above ground or underground in a pit or a
trench. In Chapter 5 different methods are described. Whichever
method is used, the heap of organic material has to be set up in a special way.

Decomposition is easier if the material is cut into small pieces and if
easily decomposable material is mixed with material more difficult todecompose.

The practice of composting19

Figure 4: Cutting the organic material into small pieces

A useful suggestion is to start the heap by a foundation of coarse plantmaterial such as twigs or sugar cane stalks. The outside air can easily
flow in under the heap and any excess water flows away more quickly.
If the heap is built up in layers, the individual layers should preferably
not be thicker than 10 cm for plant material and 2 cm for manure.
Apart from the organic material available, the way the heap is madedepends also on the individual experience and results.
Covering the heap
In an area of heavy rain the heap will have to be protected against excess water. Preferably it can be kept dry by putting a simple roof
above the heap (see figure 3) or even simpler: covering with a layer ofleaves, a cloth, jute or plastic etc. If plastic is used then only cover the
top, so that the air can penetrate through the sides. Trenches aroundthe heap facilitate the run off of excess rainwater.

Covering the top with the materials mentioned can also be an advantage in dry areas. It prevents excess evaporation of moisture from theheap and it dries out less quickly.

20

The preparation and use of compost

Air channels
It is good advice to put air channels into the heap. This can be done
effectively by putting stakes or bundles of twigs, straw or other firmmaterial upright in the heap when composing it. The bundles can remain inside, because they let in enough air, but stakes have to be removed as soon as the heap has been completed.

These air channels should be about 12 cm in diameter and about 1 m
apart. After 4-5 days the channels have to be closed up. If there is toomuch ventilation the fermentation process can turn into a detrimental
combustion process.

The practice of composting21

5

Methods to make compost

There are many ways of making compost. In this chapter different
methods are given. We have gratefully made use of materials of
HDRA and KIOF in order to be able to present many different methods of compost making in this Chapter.
Taking into account the factors mentioned before, such as availabilityof organic materials and weather conditions, a choice can be madefrom these methods.
In the long run everyone must work out a method to suit oneself. We
advise you to experiment and find the method that suits best to yoursituation. Of course you can always contact Agromisa, HDRA or
KIOF ask for specific information. The addresses are given in the section Useful Addresses.

5.1

Indore method

The Indore Method is much used for composting in layers.
Building the heap
The basis of the heap should consist of twigs and cane shoots. The
following successive layers are piled on top of this:? a layer of about 10 cm tough organic material which is difficult todecompose;? a layer of about 10 cm fresh organic material which decomposes
easily;? a layer of 2 cm animal manure, compost or slurry from a biogastank.
? a thin layer of soil; the soil should be collected come from the top
layer (top 10 cm) of clean (moist) soil (e.g. from under trees). This
ensures that the right micro-organisms are brought into the heap.

22

The preparation and use of compost

This sequence of layers is repeated until the heap has reached a final
height of 1.5 to 2 meters. In this way the heap is composed of manylayers. Building the heap should be done quickly, preferably within aweek. See figure 5.

Figure 5: Example of an Indore compost heap
Turning overDuring decomposition the heap has to be turned over regularly, in order that it remains well aerated and all the material is converted into
compost.

The first turning over of the heap should be done after 2 to 3 weeks.
The heap is broken down and built up again next to the old heap. The
layers are mixed and the heap is, as it were, turned upside down andinside out. Again, a foundation of coarse plant material is made first.
Then the drier and outer, less decomposed part of the old heap isplaced in the central part of the new heap. The drier material will haveto be watered before the heap can be built up further. This core is covered with the rest of the material. The original layered structure is lost.

Methods to make compost

23

The second turning over takes place after 3 weeks and it may even benecessary to turn the heap over again for a third time. Repeat the
moisture test and the temperature test a few days after each turningover operation.
Time for decomposition
Decomposition is complete if the plant material has changed into an
unrecognizable crumbly, dark mass. Twigs and thick stems do not decompose completely and can still be seen. Under favourable conditions, the decomposition process in the Indore Method takes 3 months,
but under adverse conditions it may take longer than 6 months.

Some substances, such as human urine and wood ash promote thegrowth of the micro-organisms. A small amount of these in the heap issufficient to accelerate their growth. If the process has to be speededup spread some urine or wood ash over the thin layers of soil, but onlyin small quantities; too much ash kills the micro-organisms. Urine,
diluted with water 1:4 is sprinkled over the heap, using a watering can.
The Indore Method usually gives good results.
The advantages of this method are:? the process can be kept under control and runs smoothly, because
the heap is turned regularly;? compost is produced in a short time.
Disadvantages of this method are:? it requires much water;? it is very labour intensive.

5.2

Bangalore method

The Bangalore Method is another popular composting method. The
heap is constructed in a similar way to the Indore Method. Here too, acompost heap of several layers is set up in a week’s time.
It differs from the Indore Method as follows:24

The preparation and use of compostA few days after completion of the heap, it is completely covered with
mud or grass sods, thus closing it off from outside air. Decompositionof organic material continues, but now other types of micro-organisms
keep the process going. These micro-organisms decompose the material much more slowly. Therefore, it takes longer before compost isformed than in the Indore Method, although the quality of the compost
is about the same.
The major advantages of the Bangalore Method are:? a saving of water;? it requires less labour, because the heap is not turned over during
the decomposition process.
Disadvantages of the Bangalore Method are:? more disease germs and weed seeds survive due to the temperatureduring decomposition;? the decomposition process is more difficult to control because theheap has to be kept continually covered;? it is a less suitable method for those with little or no experience incomposting.

5.3

Heating process or block method

This method resembles the Bangalore Method. However the treatment
is different and it can be used to compost large quantities of organic
material.
A continuous heap system
The Heating Process Method is based on a continuous heap system.
That is to say, new heaps of organic material are being made all thetime, piled up and treated in the following manner (See also figure 6):

On the first day a heap is made of all available material. This heap hasa ground surface area of 1 x 1 meter minimum and 3 x 3 meter maximum and a height of about 1 meter.

Methods to make compost

25

Leave the heap to stand for two days.
Within the heap decomposition starts on its
own accord. After these 2 days (Figure 6:
day 3), the air is forced out of the heap bytrampling over it. The heap is deprived ofso much air that an almost comparable
situation occurs as in the covered heap of
the Bangalore Method.
On day 4 a new heap is built on top of thefirst heap. This new heap cuts the first heap
off completely from the outside air.
In the Heating Process Method a new heap
is made every day. In fact, on the second
and third day a new heap is made next to
the first one. On the fourth day a heap isbuilt on top of the first one. It follows thaton day 5 a new heap is put on to the second
one. The procedure is clarified in figure 6.
And so on.
Advantages:? it is a simple method for large quantities
of organic material;? it is a continuous method.
Disadvantages:? only suitable for large quantities of material;
Figure 6: The healing? requires much labour and material;? more chance that disease germs and weed process or Blockseeds survive the decomposition process Method (Source:
HDRA)
at lower temperatures;? the process is more difficult to check;? requires much experience and insight in composting.

26

The preparation and use of compost

5.4

Pit composting

Figure 7: Process of pit compostingThis method involves making compost in pits that have been dug in
the ground. The best depth for a pit varies according to local soil conditions and the depth of the water table. A typical pit would measure
1.5 to 2m wide, 50cm deep and any length. The pit can be lined with athin layer of clay to reduce water loss. Often, several trenches are dug
next to each other, to allow turning from one pit into the next.
Material should be placed in the pit in layers as described below. For alarger pit measuring 2m wide, 2m long and 1 m high, 1 to 1.5 litres ofwater should be poured on before applying the layer of soil, which
seals the pit.
The layering is as follows:1
10 cm of material, which is difficult to decompose (twigs, stalks)
2
10 cm of material which is easy to decompose (green and fresh)3
2 cm of animal manure (if available)
4
A thin layer of soil from the surface of arable land to obtain the
micro-organisms needed for the composting process5
Repeat these layers until the heap reaches 1 to 1.5m high6
Cover with grass or leaves (such as banana leaves) to prevent
water loss.

Methods to make compost

27

After 2 to 3 weeks, all the contents of the pit should be turned over
into the second pit and 2 to 3 weeks later this should be turned into thethird pit. As the decomposing material from pit 1 is turned into pit 2,
new material, which is ready for composting, can be put into pit 1,
thus creating a process of continual compost making.
Advantages:
Pit composting is quick, easy and cheap as it does not require investment in materials. It needs less water so it is useful for dry areas.
Disadvantage:
It is more difficult to follow of the decomposition process than with an
above ground heap.

5.5

Trench composting

Trench composting is similar to pit composting except that plants aregrown directly onto the trench as opposed to taking the compost out ofthe pit and spreading it on land. A trench should first be dug. The size
depends on how much material you have available and how many
plants you are planting in the trench. The width can range from 50cm
to several meters, the depth lm or less and it can be any length. It
should then be filled as follows:
1
2
3
4
5
6

28

10cm of material which is difficult to decompose (stalks or crop
residues)
10cm of material which is easy to decompose (fruit and vegetable scraps)
Add 2cm of animal manure (if available)
A thin layer of soil from the surface of arable land to obtain the
micro-organisms needed for the composting process
Repeat these layers until the pile is about 50cm above the groundCover with soil, grass or leaves (such as banana leaves) to prevent water and nutrient loss and leave to settle for about one
month before planting.

The preparation and use of compost

Advantages:
Trench composting is especially useful against termite attack as most
species live above ground level.

5.6

Basket composting

Figure 8: Baskets with compost and seedlings planted aroundthem (HDRA)

If materials for composting are in short supply, you can still makegood use of them by using the basket method of composting. It is especially useful for food production in home gardens. The method is asfollows:
1
2
3
4
5
6
7
8

Dig circular holes 60 cm in diameter and 60 cm deepLine the bottom with material which is difficult to decompose(twigs, stalks)
Add 8 cm of animal manure
Add 15 cm of green vegetation (young leaves that have a highwater content)
Add 0.5 cm of ash
Repeat steps 3 to 5 until the hole is full
Cover with grass or leaves to prevent water and nutrient loss
Using thin sticks and weaving them together, mark the circularoutline of the pit with a round ‘basket’, 10cm in height.

Methods to make compost29

Seeds or seedlings can then be planted around the basket structure.
The plants will make use of the nutrients in the compost.
If you build more compost baskets in your garden, place them in different areas every time so that the whole garden becomes more fertile.
Advantages:
Basket composting makes good use of nutrients for a small kitchen
garden. This method is also good for using up small quantities ofwaste.

5.7

Boma composting

Figure 9: A boma with bedding for composting (Source: MullerSamann & Kotschi, 1994)

When a farmer keeps animals, there is usually, a boma (enclosure
where the animals are kept all the time or only at night) on the farm.
In order to keep the animals clean, bedding is put in the boma.
It as advisable to add enough new bedding once a week, so that all
urine is soaked up. Any type of dry organic material can be used as
bedding. It can be maize stalks, weeds, dry grass or leaves, sawdust,
etc.
30

The preparation and use of compostA mixture of materials is best. Bedding soaks up urine and droppings,
which are very rich plant food, and prevents losses through leachingor drying out of manure. The farmer who puts new bedding regularly
will make plenty of high quality compost.
Well-mixed manure can be taken out either every day or once a week.
If taken out daily, the mixture should be put in a pile and a small
amount of soil spread on top each day. This can be continued until
there is enough material to build a boma compost.
KIOF has described the following method for making boma compost:
Each time manure is taken out of the boma, it should be composted
immediately. Sheep, goat, rabbit and chicken manure are all rich manure. Because the bedding is plant material, there is no need to add
more greens. It is practical to make the compost next to the boma tosave effort moving the manure and used bedding.

Figure 10: A boma and compost site (Source: KIOF and HDRA)

1 Like on the drawing, a trench of 30 cm in depth is dug out behindthe boma (A). The soil is put next to the trench. The bottom of thetrench is loosened and a layer of dry vegetation is put on the bottom.
2 Then a layer of about 10 cm manure and bedding is thrown out of
the boma into the trench.
3 This is covered by about 5 cm of soil.
Methods to make compost31

4 Again a layer of about 10 cm manure is added and again covered bysoil. This goes on until the compost pile is completed.
5 In the dry season the manure will need watering. During the rains
the manure will be very wet. When this is the case, keep the pilelow (about one meter). Dry manure can be piled about one-and-ahalf meters high.
6 When finished, the whole pile is covered with soil and finally withgrass, maize stalks or banana leaves to prevent drying up.
7 Make sure you use sticks to control the temperature because boma
manure becomes very hot. Add water as soon as the stick feels dry
or becomes white.
8 After two or three weeks the pile is turned into the second trench(B) and after two or three more weeks it is turned into the third
trench (C).
9 The compost is stored until planting time, in a big, covered pile next
to the third trench (D).
Note: If a boma has no roof the manure becomes wet during the rain.
To avoid leaching, all manure should be taken out as often as possible
and immediately composted and covered. Remember, compost should
be moist, not wet.

32

The preparation and use of compost

6Composting specific materials

Composting a mixture of organic wastes makes decomposition easierand produces a more balanced end product. Sometimes there is a large
quantity of one type of material and there is little chance of this being
mixed with other materials. However if dealt with properly these materials can make good compost.

6.1

Composting water plants

Waterweeds can be a considerable
problem in lakes and waterways,
which are becoming more and more
unbalanced and disturbed. Such problems often arise when the surface water becomes enriched with nutrientsand the introduction of exotic plants,
the water hyacinth, Eichnornia crassipes, for instance.
Controlling these waterweeds withherbicides is harmful to the environment, expensive, and a waste! Indeed,
they can become a valuable soil improver if composted as follows:
Figure 11: Water Hyacinth
1 Harvest waterweeds and spreadthem out for a few days along thewater’s edge to dry, until the weight has about halved.

2 A compost heap can be made, using the wilted plants, soil, ash,animal manure and household waste (kitchen scraps).
3 Use the Indore method (Section 5.1) of composting by placing
twigs at the bottom and building up the different layers to form aheap. This will help prevent the heap from being too wet.
Composting specific materials

33

4 Turn over the heap regularly; every two weeks.
Compost made with water hyacinth only, may in some cases reduceyields. Test the compost in small amounts before applying to a crop.

6.2

Composting seaweed

Figure 12: An adult Giant Kelp (Macrocystis) plant

Seaweed has been used as a fertilizer since long. For those farmers
who are close to the sea, it can be very useful. Many species are
known and it is found in most seas.
Seaweed is a potential fertilizer, which is literally waiting to be‘picked up’. It contains many trace elements and growth regulating
substances, which are highly beneficial to crops.
Removing the salt
The main requirement when composting seaweed is to remove most of
the salt. This can be done simply: In the rainy season seaweed is collected seaweed and spread out or put in small heaps. After some time
the rain washes out the salt.

34

The preparation and use of compostDirect use of seaweed as a fertilizer
The simplest method of application of seaweed as a fertilizer starts
with the drying of the seaweed, after which it is ground. The powder
thus obtained can be used directly as a fertilizer.
Composting
The other fertilizer application of seaweed is composting. If the seaweed is wet then it should be mixed with a large amount of dry material such as straw. Dried seaweed can be used in a normal compost
heap. Generally the decomposition of seaweed is very quick.

To summarize, for farmers along the coast, seaweed is a potential
source of manure. The seaweed will always have to be de-salted first.
Seaweed can bring about a reasonable yield increase, but is not a
wonder cure. The working of growth regulating substances is again
very dependent on the soil type to which these are applied.

6.3

Composting coffee pulp

Figure 13: Elevated compost heap (Source: HDRA)

In coffee producing areas, large quantities of coffee pulp are a problem. The fermenting piles give off unpleasant smells; breed flies andpollute waterways. Coffee pulp is a good fertilizer as it is rich in organic matter, nitrogen and potassium. Some growers spread the heavy

Composting specific materials

35wet pulp on their coffee plantations but there can be problems withtransport and spreading and this can lead to smells and plant growth
problems.
It is much better to compost the material first so that it can be used
more effectively.
Good aeration
This dense material needs good aeration so a number of above-ground,elevated heaps should be constructed. These elevated heaps need to beroofed or covered to stop too much water from entering the compost
heap. The elevated floor can be made of bamboo poles mounted onbricks or stones.

Before composting, the pulp needs to be drained and loaded into thepits to a height of about one meter. Vegetable waste can be mixed in if
available as well as some soil or compost. This is to obtain the rightmicro-organisms that decompose the waste. The heap should be turned
every 4 to 6 weeks and the compost should be ready in 4 to 6 months.

6.4

Composting domestic waste

Domestic waste includes any kind of decomposable household waste
such as kitchen scraps, paper, sweepings or wood ash. It should notinclude meat or slaughter wastes. These attract vermin and insects andgive an unpleasant smell. Neither should it include excreta from humans, cats or dogs as these contain toxins, which can be harmful if notcomposted properly (see section on human waste composting). It isalso better not to use too much of the same type of material.
Remember that the composition of domestic waste is culturally andregionally defined. In Asia, in particular, composting of household
waste is an old technique.
Composting in a heap
Most domestic waste is produced in small quantities, but at regularintervals. It is advisable not to put small amounts on the heap every
day, but to save it before putting it on the compost heap.
36

The preparation and use of compost

As a guideline: add a new layer when you have enough material to
make a layer of about 30 cm thick. Extra material could also be collected to add to the heap, but this costs time and energy. Because theamount of organic waste available is often small, only a small compost heap can be made.
Since most domestic waste has little structure (such as food remains
and wood ash) it is likely that aeration will be poor. Therefore, when
composting domestic refuse, considerable attention has to be given to
ventilation of the heap. See section 4.3 and 4.6 - subsection on air
channels.
Composting in a barrel
In Mali at the institute IPR/IFRA (address in the section Useful Addresses) a method has been developed to make compost from domestic waste in a barrel.

Using barrels might make it easier and more hygienic to practice composting near the house. The barrel also regulates the air, humidity andtemperature during composting.
? Preparing the barrel
Paint the inside of the barrel to prevent it from rusting.
Make three holes (1 cm in diameter) around the top third and thebottom third of the barrel, at a distance of 52 cm from each other.
Make another hole of 1 cm in the base of the barrel. Through thisbottom hole the liquid from the decomposing organic matter canseep from the barrel. If it stayed in the barrel the material at the bottom will start to rot, which causes a bad smell and not good compost.
Remove the top; it is used as a lid for regulating the compostingprocess when the barrel is filled. As the organic materials decom-

Composting specific materials

37pose, it will shrink in size, and the lid
will slide down and close the barrel.
Make an opening about 20 cm above
the base of the barrel, 65 cm highand 20 cm wide, so that you cancheck on how the composting is progressing. You should normally keep
this opening covered. Place the barrel
on a tripod stand of 25 cm high, sothat you can put a vessel underneathto catch any fermented liquid.
? Method of making compost
Figure 14: Barrel adjusted
It is best to work with two or three for compost making
barrels: the first can be used for an
initial compost, which is sieved and put in the second barrel for further composting. The third barrel is used to store ready-to-use compost. There is no need to make holes in the second and third barrels.
Any organic matter can be used to make compost in the barrels, especially domestic waste. Cut the organic matter into small pieces
before putting it into the barrel and mix the different materials. If
you have enough material, you can fill the barrel in one go otherwise you can fill the barrel slowly.
An improvement to the process is to collect the liquid that seeps
from the barrel through the bottom hole and add it again to the decomposing organic matter in the barrel. In this way the loss of nutrients is diminished to a minimum.
? Filling the barrel in one go
If you fill the barrel in one go, the humidity of the mixture in thebarrel will stay more or less constant. Air will enter through theholes in the barrel. After 4 or 5 days you can turn the mixture into
the second barrel, in which it will stay for 8 to 10 days. After that38

The preparation and use of compost

period the compost will probably be ready. Of course the time forthe composting process depends on the climate (temperature).
The IPR/IFRA has developed a recipe using the method described above.
Compost the following materials:
52 kg of sawdust
1.7 kg of poultry manure
2.5 kg of natural Tilemsi phosphate
800 ml of urine.
After 45 days the composting should be well advanced.

? Filling the barrel slowly
If you fill the barrel slowly, you have to count the number of days
for the process from the time when the barrel was filled to the top.
Then after 4 to 5 days the mixture is sieved. The fine material canbe put into the second barrel. The large pieces and any not yet decomposed material is put back in the first barrel, which you can fillup again slowly.

6.5

Composting human waste or sewage

Composting human waste or sewage is a useful way to dispose of it
and it is a good source of nutrients for plants. There are however anumber of problems in dealing with human waste or sewage. Diseases
can spread through handling the waste and through the consumptionof the crops grown on this composted human waste.
It is very important to use appropriate methods when dealing with it
and to have previous experience of the composting process.
The mentioned problems should not prevent the use of human waste
or sewage in a compost heap. In this book we do not explain in detail
how to compost human waste. If you want to experiment, we refer you
to the books mentioned in the section ‘Further Reading’. You also canwrite for more information to either Agromisa’s Question and Answer
Service or the HDRA Overseas Advisory Section (See the section‘Useful Addresses).

Composting specific materials

39

7

Putting compost to use

Some of the many uses of compost are given in this chapter.
Examples are:? fertilizing;? potting soil, nursery soil, planting trees;? erosion prevention;? fish feed.
? mushroom growing - (not treated in this Agrodok).
When the compost is ready, it can not always be used straight away
and it has to be kept for a while until it can be put to use. Care has tobe taken that the compost does not lose its fertility during storage.
Caring for the stored compost
Compost should never be left uncovered in the rain or in the sun. The
rain washes out the nutrients and the sun can cause burning. The compost then loses its fertility. To reduce this loss the compost should becovered. Some useful covers are: banana leaves, intertwined palm
leaves or a sheet of plastic. If the compost is left too long, it may also
become a breeding place for unwanted insects, such as termites andthe rhinoceros beetle (Oryctes rhinoceros).

7.1

Fertilizing

The advantage of using compost for fertilizing is that it improves soil
fertility in the long run, by improving the soil structure. Organic matter is the key factor in improving the soil structure. Organic matter
contains a lot of micro-elements important for plant growth and it improves the water retention capacity of the soil. Another aspect is thatcompost releases the nutrients slowly, which means that the effect ofcompost is one in the long run.
Artificial fertilizers contain only a few nutrients (Nitrogen, Phosphorus and Potassium) but of these nutrients the concentration is far

40

The preparation and use of compost

higher than in compost. Nutrients from artificial fertilizer are released
quickly. This means that artificial fertilizers are a quick one-off supplyof nutrients to satisfy the needs of a crop.
Adding artificial fertilizer alone is not sufficient to retain a sufficientlevel of soil fertility. Organic matter is needed to retain the water andnutrients. In a degraded soil, where there is no organic matter, yields
will still decrease, even if artificial fertilizer is added. This means thatwhenever artificial fertilizers are being used, the farmer needs to takecare of the organic matter content of the soil. An integrated approach,combining the application of compost with an application of artificial
fertilizer is a good strategy when a crop quickly needs nutrients..
In the long run artificial fertilizers might even have a negative effecton the soil, because the soil might become exhausted and degraded if
no organic matter is added and it might become acid because of thechemical composition of the fertilizer. See also Agrodok 2 : ‘Soil fertility management’.
Application at location where needed
If compost is to be used for direct fertilizing of a field crop on a large
piece of land, a very big quantity will have to be applied. This is a disadvantage of compost.

Figure 15: Vegetable garden

Putting compost to use

41

Using compost in the vegetable garden, or on small plots of land isvery suitable. It is important to take care to apply the compost locallyat the specific places where it is needed.
For example:? When preparing a sowing bed the compost can be mixed superficially through the top soil. The fertile compost is then easily available for the seedlings.
? Apply compost in pits or trenches in which the crops are planted.
This method is particularly useful in dry regions. The crop is planted
in pure compost or compost mixed with top soil.

7.2

Nursery soil, potting soil, planting trees

Compost is very beneficial for nursing seedlings, either in a seedbed
or nursery where they germinate, or in pots or pits where young plants
and trees are planted. Compost retains the water well, so young plants
will not easily get stressed by water shortage, and they get all the nutrients they need from the compost.

Figure 16: A nursery bed madeof compost

42

Figure 17: Pots filled with compost

The preparation and use of compost

Figure 18: Tree planting: compost is put in the holes in which thetrees are planted. Cover the compost again with the soil from thebottom of the pit, to prevent the compost from drying out. See also
Agrodok no. 19: Propagating and planting trees.

7.3

Erosion prevention and erosion control

The use of compost to prevent erosion is strongly linked with improving soil fertility. A fertile soil is in general less susceptible to erosion,
because the organic matter holds the soil together. In addition compost
used as a ground cover counteracts splash erosion caused by rain. See
the Agrodok no 11: ‘Erosion control in the tropics’, to read more about
the role of organic matter in reducing soil erosion.
Collecting water run off
A measure to control erosion by means of compost is to make welldrained ditches parallel to the contour and fill them with compost tocollect the water run off.

7.4

Compost for fish feed

Compost is a good type of fish feed, through fertilizing the fish pond.
The naturally occurring food in the fish pond consists of very small
plants (algae or phytoplankton) and very small animals (zooplankton).

Putting compost to use

43Compost (or manure) is added to the pond as an indirect feed for fish.
It accelerates the growth of the plankton in the water. Many fish species, such as the Tilapia sp. and Carp sp. (Cyprinidae) feed on plankton. In general fish respond well to the addition of fertilizer and their
numbers may rise considerably.
Managing the pond
The water in a pond must be of good quality so that the fish will behealthy and grow well. In order to grow, fish need oxygen. This is
produced mainly by the algae floating in the water; if a large amountof algae is present, the water will have a green colour.

Good fertilizer practice is important to maintain water quality and tomaintain a good amount of naturally occurring fish food available in
the water. The amount of fertilizer added to the water depends on thenumber of fish in the pond. If too little fertilizer is put in less natural
food will grow and less fish will be produced. Putting in too much
fertilizer or fertilizing irregularly can lead to oxygen shortage (because
the algae and plankton use oxygen during the night) and fish will die.
Application of compost to the pond
Compost should be applied at least once a week, and it is best to do
this every day. It is important to spread the compost evenly over the
pond in order to ensure optimal use by the algae and plankton so thatthey can multiply.

In practice coarse organic material is often added to fish ponds. Muchof this starts to rot, using up a lot of oxygen from the water. In thiscase it is very likely that the fish will not be able to get enough oxygen
and will suffocate.
Using compost instead of coarse organic waste material is advantageous, because compost is ready decomposed material. When compost
is added to fish ponds, the oxygen level does not decrease much.
There are two reasons for this: compost uses only little oxygen andadding compost induces strong growth in phytoplankton that produce

44

The preparation and use of compost

oxygen. Because of these positive effects, much more compost thanfresh organic refuse can be added to the water without difficulty, andmore fish can be produced. Compost can also be directly consumed bysome types of fish, which is not the case for fertilizers.
In conclusion, compost appears to be one of the most ideal feeds for intensive
fish ponds. There will be no shortage of oxygen so more feed can be added
and much higher yields can be attained.

A well-managed and fertilized pond can sustain 3 kg fish per 100 m²
per day. In practice this amount is usually lower.
In some places composting is done in the corner of a pond. Thismethod is less effective than making compost on land and then spreading it afterwards over the whole pond. Fish production is higher using
the latter method. This is probably because the nutrients from a compost heap in the corner of a pond are not spread well throughout thepond.
Fish food from composted Water Hyacinth
Fish food made from composted Water Hyacinth (see section 6.1),
dung and rice straw fed to Nile tilapia can give a production level of360 kg per 100 m². The following recipe is used for the compost:? Dry 1,000 kg of water hyacinth in the sun until the weight is reduced to approximately 400 kg. Then mix the dried water hyacinth
well and spread it over a layer of (rice) straw measuring 3 x 3 m.
Make the compost heap about one meter high and drive bamboo
sticks through it so that air can reach the inside.

? Mix the compost heap every two weeks by bringing the material at
the bottom up to the top and the material at the top down to the bottom. After two months the compost will be ready to be spread overthe pond.
To harvest 25 kg Nile tilapia from a pond of about 100 m² after six
months, you need to feed them 2 kg of compost every day. For these

Putting compost to use

45quantities you will need four compost heaps of the size describedabove.
See also:
Agrodok no 15: ‘Small-scale fresh water fish farming’ for more general information on fishponds, and,Agrodok no 21: ‘On-farm fish culture’ for detailed information on integrated ways to feed fish.

46

The preparation and use of compost

8

Liquid manure and plant teas

The aim of making liquid manure and plant teas is to quickly provide
a crop with adequate natural plant food during the growing season.
Liquid manure and plant teas are ready for use after two or three
weeks, as compared to six weeks or more for compost.
Liquid manure and plant teas may seem unnecessary in an organic
system, where emphasis is on feeding the soil, not the plants. There
are occasions, however, when liquid feed is the only answer, such as
when roots have been damaged and cannot take up enough nutrients.
Liquid feed from animal manure or a plant as comfrey (Symphytum
spp., French: Consoude) supplies nutrients fast.
A liquid feed is also essential when plants are grown in the restrictedenvironment of a pot or plastic bag.

8.1

How to make liquid manure and plant teas

Note: the instructions for plant teas begin at number 3.
You will need the following materials and equipment:? Manure – either chicken or rabbit or a mixture of both
? A container – a drum or half a drum (bucket) for small quantities? One strong bag or gunny bag? One strong pole and rope
1 Put the chicken manure or rabbit manure (or a mixture of both) in astrong sack or gunny bag with 50 kg of manure for one drum of water. Fill it in such a way that you can tie the top of the bag securely.
2 Suspend the bag containing manure in a container full of clean water. The bag should be tied securely with a rope and suspended on astrong pole placed across the top of the drum.

Liquid manure and plant teas

47

Figure 19: Making liquid manure (Source: KIOF)

3 When preparing plant teas, branches and green sappy leaves arechopped up and placed in a drum, full of clean water. It is not necessary to put the leaves in a bag.
4 Leave the manure (for the liquid manure) or chopped leaves (for theplant teas) to stand for 15 days. Cover the drum to prevent excessive evaporation.
5 After three days and every other day thereafter, stir the liquid in the
drum. For liquid manure stir by lifting the bag several times using
the pole.
6 After 15 days the water will have turned blackish and most of theplant food (nutrients) in the manure will have been dissolved into
the water. Remove the bag.
7 Dilute the contents of the drum 1:2 (to one part of the liquid manureor plant tea add two parts of clean water). Spray the crop at the stemand not at the leaves.

48

The preparation and use of compost

8 Water the crop with this liquid manure or plant tea for two or three
weeks. It is effective as top dressing after planting the crop using
compost.

Figure 20: Making liquid tea (Source: KIOF)

Liquid manure and plant teas

49

9

BokashiBokashi is an organic fertilizer, which is made by fermenting organic
matter. The name Bokashi is a Japanese word, which means: fermented organic matter. Bokashi contains a lot of nutrients and it
serves as a rapid working fertilizer. You can compare it with an artificial fertilizer like NPK. Traditionally Japanese farmers use Bokashi toimprove soil fertility and supply the crops with nutrients.
Bokashi is made through fermenting organic matter either in the open
air or in a closed off situation. In the open air the mixture is in contact
with oxygen from the air; this is called an aerobic situation. It is comparable with the normal composting process. When the fermenting
mixture is closed off from the air (in plastic bags for example) it iscalled an anaerobic situation.
The organic matter for the Bokashi fermentation needs special selected ingredients (rice bran, wheat bran, fish meal, etc.), together withorganic waste materials. Bokashi has been developed in Japan by Prof.
Teruo Higa.
Bokashi compared to compost
The fermentation process of Bokashi conserves nutrients in the organic material better than the process of decomposition that takes
place when composting. The reason that nutrients are better conservedis that during the fermentation process, the temperatures does not become as high as in the normal composting process.

In the anaerobic Bokashi fermentation process temperatures rise toabout 40 oC , while in the aerobic process and in the normal composting process temperatures can rise to about 70 oC and possibly higher.
This means that in the anaerobic process the conservation is even better than in the aerobic process. However, when you use the anaerobic
process it is difficult to prepare large quantities of Bokashi, this is easier when using the aerobic process.

50

The preparation and use of compost

Bokashi is made in a short period: 6-8 days in a tropical climate and 23 weeks in a more temperate climate. It can be applied to the soil directly after preparation, although you should wait 14 days before
planting or sowing.
Effective Micro-organisms
The important aspect of Bokashi preparation is adding Effective Micro-organisms (EM). This is an artificially prepared mixture of useful
soil micro-organisms. When aplied to the soil these effective microorganisms settle in the soil and will oust the harmful micro-organisms.
It improves the effectiveness of the organic matter in the soil and thesoil fertility will be improved.

The Effective Micro-organisms can be bought from the institutes
where Bokashi is developed and researched. You can find addresses inthe section ‘Useful Addresses’. If you cannot get hold of the EM mixture it is also possible to use clean soil; preferably fresh, moist soil
from a forest. This soil contains a lot of micro-organisms and is mostprobably not polluted with chemicals. Although this will not be as effective as the artificially selected EM, it can still give you an adequate
result.

9.1

The organic materials

For making Bokashi you can use any type of organic matter. Use atleast 3 different materials to enhance the diversity of micro-organisms.
It is important to have a combination of materials that have either a lotof nitrogen (low C:N ratio) or carbon (high C:N ratio). The quality ofBokashi is improved by adding finely ground sea shells (chalk meal)and Bentonite clay minerals to the fermenting mixture.
N-sources
Poultry manure is a good source of Nitrogen. Other types of manure(cow manure, donkey manure, pigeon manure, etc.) can be used aswell, though the quantity has to be multiplied by 1½ .

Bokashi51

Alternative sources of Nitrogen are fish meal, bone meal, or nitrogen
fixing plants (leguminous plants), e.g. Mucuna, Crotalaria, Leucaena
leaves, etc. These plants have to be dried and cut into pieces before
being used. They also contain other important nutrients.
Carbon Source
Rice bran is a good source for carbon. It contains carbohydrates andphosphorus too. Rice bran is important because it is a good stimulant
for the fermentation and it feeds the micro-organisms well. Instead ofrice bran you can use other types of bran like wheat bran and maizebran or root crops, such as cassava, yam or potatoes. These need to be
cut into small pieces before using. Alternatively, fruits as bananas canbe used too. Straw, weeds and sawdust are also sources of C.
Charcoal
Charcoal is a porous material, which increases the nutrient holding
capacity and improves soil structure. It also acts as harbouring point
for the micro-organisms. If charcoal is not available you can use straw,
kelp (dried sea weed) or bean husks. An alternative is to roast ricehusks.

Do not use ash; this decreases the activity of the micro-organisms.
Sugar cane trash
Adding sugar cane trash (bagasse) to the Bokashi ensures a good air
supply and water retention during the fermentation process. It also
retains the nutrients such as Nitrogen. Alternative materials for thisare: rice husks, coffee husks, wood chips/shavings, maize cobs, driedgrass.
Effective Micro-organisms
Old Bokashi contains a lot of micro-organisms; these micro-organisms
start the fermentation process. The artificially prepared mixture of Effective Micro-organisms can be bought from the institutes of which
you can find the addresses in the section ‘Useful Addresses’. If you

52

The preparation and use of compost

make Bokashi for the first time and you cannot buy the EM mixture
easily, use clean and moist soil, preferably from a forest.
Molasses
Molasses is a by-product of sugar production. It contains a lot of energy and stimulates the fermentation process by feeding the microorganisms. An alternative is using sugar or honey, but of course theseare much more expensive.
Humidity
The production of Bokashi needs little water. If Bokashi is too wet, it
stinks. For the recipe that is given in the next section, 20 litres areneeded. The amount needed depends also on the moisture content of
the materials.

The moisture content should be 30-40%. You can check it by squeezing a handful of the mixture. Water should not drip from the squeezed
mixture, but it should remain as a single unit without crumbling.
However, on touching it should crumble easily.

Figure 21: Checking the moisture content

9.2

Preparation of bokashi

If you need to prepare large quantities it is easiest to use the aerobic
process. For preparing small quantities it is advisable to use the anaerobic process, because more nutrients are retained.

Bokashi53

In the recipe below, organic matters are specified, using the information in the last section you can vary these materials and experiment tofind the best way of preparing Bokashi in your specific situation.
Aerobic method
A recipe for the aerobic preparation of Bokashi (from Costa Rica):

What you need:? 1 bag of poultry manure (Nitrogen-rich material)? 1 bag of rice bran (Carbon-rich material)? 1 bag of charcoal (small pieces 1-2 cm)? 1 bag sugar cane trash? 2 liters molasses? ½ bag of Bokashi or compost (containing EM)? 2 bags of clean soil
? water
Mixing:
It is important to mix the materials well. A good way to do so is:? Cut all the materials into fine pieces and put them into piles.
? Dissolve the molasses in water (20 l); heating may make it dissolve
easier.
? Spread out a layer of one of the materials: Use one third of thequantity of the recipe for one layer.
? Water the layer with the molasses solution. Use a watering can.
? Put another layer of a different material (1/3 of the quantity) on topof the first layer.
? Water this layer too with the molasses solution.
? Continue this process until all the materials are used.
? When you have one heap of the moistened materials, turn the heap
over again to increase the mixing of the materials.
? Finally make a heap of about 50 cm high. In colder areas this might
be a bit higher to reach high enough temperatures in the heap. (Inwarmer areas the heap might be a bit lower for the opposite effect).

54

The preparation and use of compost

? Cover the heap with sacks or mats. Don’t use plastic because the air
can’t pass.
? Turn the heap over, every 12 hours. Do it in such a way that the material, which was on the outside, ends up in the inside and the otherway round. If the heap is very hot, turn it over a few times to lower
the temperature. After one day the mixture will be brown, and when
taking away the cover you probably see fungus growing.
? After the third day take the cover off the heap in order to let the
mixture dry. The colour will change from brown to greyish. The
heap will have a sweet-sour smell.
? Continue to turn over the heap every 12 hours, to let it dry more
quickly. Dry the Bokashi very well.
Preparation time
In tropical areas the aerobically prepared Bokashi is ready after 5-7
days. In temperate climates it will take longer, possibly 2-3 weeks.
The colour is grey and the texture is fine and like dust.
Storage
Direct use is preferred, but it can also be put in sacks and stored forabout 3 months in a dry, well-ventilated place, out of the sun.
Anaerobic preparation
If you need to prepare only small quantities it is advisable to use theanaerobic process.

The start of the preparation, the mixing and the watering is the sameas in the aerobic process. When the mixing is done, you have to packthe mixture in large black plastic bag or container. Close these air
tight. Don’t put them in direct sunlight.
The Bokashi is ready when it has a sweet smell of fermented matter(beer or wine smell), and when you see white fungal growth. If thesmell is bad (rotten), the Bokashi is not well fermented and should not
be usedBokashi55

Preparation time
The time needed for fermentation is 3 - 4 days in tropical areas and 78 days in temperate areas.
If the Bokashi production is not successful, try out various types and different
quantities of materials.

9.3

Applying bokashi

Bokashi is used in the same way that artificial fertilizers are used. It
can be applied to the soil directly after preparation, although you
should wait 14 days before planting or sowing.
Dig the Bokashi into the soil 5-10 cm deep. It is important to cover the
Bokashi with soil because the micro-organisms don’t survive sun
shine.
? For most vegetable crops it is sufficient to apply the Bokashi threetimes during the growing season. Adding handful (30 grams) to thesoil 15 -20 cm away from the roots of the plants.
? Apart from using Bokashi in vegetables it is of good use in coffee,
banana and tobacco plantations, etc.
? For field crops on average 100 - 200 gram of Bokashi per square
meter is sufficient. If the soil has a low content of organic matter
add more Bokashi. A maximum application is 1 kg per square meter.
? Bokashi can also be added to planting holes. Cover the Bokashi
with soil before planting the seedlings.
Bokashi should never be in direct contact with the plant stems or roots: Afterappying it to the soil, wait 14 days before planting or sowing.

56

The preparation and use of compost

10 Your own organic fertilizer
This chapter deals with general advantages and disadvantages of preparing your own organic fertilizer. They are not always straightforward: what may be a disadvantage in one situation may an advantage
in another situation. At the end of the chapter, a general checklist is
given as a guideline to make your own decision.

10.1 Advantages and disadvantages
Advantages? Preparing your own fertilizer is much cheaper than having to buy
fertilizers;? Organic refuse, containing nutrients, is been put to use again, otherwise it would be left to decay and the nutrients would be lost.
? An application of organic fertilizer improves the soil structure;? Soil fertility is improved in the long run: nutrients from the organic
fertilizer are released gradually over a long period;? The capacity of the soil to retain water is improved, because of theincrease in organic matter.
? Organic fertilizer contains many trace elements not normally foundin fertilizers;? Plants grown in organically fertilized soil might be more disease
resistant than in soils with artificial fertilizer only.
Disadvantages? Preparing compost, liquid manure or bokashi is very labour intensive and time consuming;? Making your own organic fertilizers is not possible everywhere. It
depends on space, available material, local conditions and other factors;
Your own organic fertilizer57

? applying compost could enhance weeds and diseases in the crop to
be grown;? a compost heap attracts vermin, such as insects, rats, mice and alsosnakes!
? the concentration of available nutrients in organic fertilizers is considerably lower than in fertilizers.

10.2 Whether or not to start preparing organic
fertilizers
Before starting to produce organic fertilizers it is important to checkon a few points to increase the chance that you will be successful andto prevent disappointments.
? Do you, or the people you work with, have enough time and energy
to invest into making organic fertilizers?
? What will you gain by starting to do so?
(Compare prices of artificial fertilizer, look at the status of the soil
fertility, etc.)? Is there enough organic material to make organic fertilizer?
(Think of the possibilities to actively seek for organic leftovers or toplant hedges or so from which leaves could be cut)? If you work with farmers, are they motivated to introduce a new
method?
? Are there cheaper and easier alternatives, such as green manuring?
All these and other aspects have to be considered. It is therefore very
advisable to discuss matters before making a start.

58

The preparation and use of compost

10.3 Practical questions as a guideline forstarting
The following practical questions can serve as a guideline when you
start making organic fertilizers:? what do people need to learn about making these fertilizers?
? where should the heap be set up?
? how big can/may the heap be?
? how much and which types of organic material are available?
? is there a regular supply of organic material ?
? what is the quality of the organic material?
? who is going to do the work?
? how much time can be spent on it?
? at times when much organic material is available, is there time touse it?
? how much fertilizer should or can be produced?
? how will the organic fertilizer be used?
? are there any taboos or other cultural socio-economic aspects whichmake it difficult to use certain types of organic material?
When you start making your own organic fertilizer, take your time to experiment, and give the first experimental process its time too.
Things will probably not go as well as they should, the first time, but in thisway it is possible to experiment and to discover the most suitable method inyour specific situation. Do not expect wonders straight away!

Your own organic fertilizer

59

Appendix 1: Composition of organic
materials
Material% nitrogen(N2)

ManuresCow (fresh)0.3
Cow (dried)
2.0
Cow urine (fresh)
0.6
Duck (fresh)
1.2
Goat/sheep (fresh)
0.6
Goat/sheep (dried)
2.0
Goat/sheep urine
2.0(fresh)Horse (fresh)
0.7
Horse
2.0
Poultry:- layers (fresh)
1.6- layers (dried)
5.0- broilers (dried)
4.0
Swine (fresh)
0.6
Swine (dried)
Swine urine (fresh)
0.4
Animal by-products
Blood (dried)
12.0
Bone ash
Bone meal (raw)
4.0Bone meal
2.0(steamed)
Fish scraps (fresh)
7.0
Hoof and horn meal 12.0
Plant residues
Ash of banana skin Ash of banana stalk Ash of cotton-seedhull
Ash of sunflower
stalk
Ash, wood
Bark, pulverized
1.6
Barley straw
0.660% phosphorus(P2O5)% potas% lime
sium (K2O) (CaO)

0.3
1.5

0.1
2.0
0.5
0.6
0.3
3.0
2.3

1.5
0.6
1.5

4.0

C/N ratio

20

0.3
2.0/5.0

0.4
1.5

0.5
1.5

0.2
1.5

1.5
3.0
2.0
0.5
5.5

0.9
1.5
1.2
0.5
1.5
0.8

2.5
35.0
22.5
25.0

1.0
0.2

4.0
2.0

-

6.5

3.3
2.3
5.5

41.8
49.9
27.0

9.5

2.5

36.0

18.5

2.0
0.9
0.5

5.0
0.5
1.0

32.5
4.7
0.4

4.0
1.0

5.6

4.1

11.4

0.5
46.0
33.0
33.0

3.0

The preparation and use of compost

8.0

80

Material% nitrogen(N2)% phosphorus(P2O5)% potas% lime
sium (K2O) (CaO)

Brewers wastes
4.0White clover, green 0.5
0.2
0.3
Red clover, hay
2.0
0.5
2.0
Cocoa shell dust
1.0
1.5
3.0
Cocoa meal
4.0
2.0
2.5
0.5
Coconut fiber waste 0.5
Coffee pulp
1.0
0.8
0.8
Cottonseed meal
7.0
3.0
2.0
0.5
Fallen leaves
0.5
0.2
0.5
1.0
Grass, immature
1.0
1.2
Groundnut meal
7.0
1.5
1.5
0.5
Maiz stalks
0.8
0.2
1.4
0.2
Millet/sorghum stalk 0.7
0.1
1.4
0.4
Melasse0.7
5.5
Orange culls
0.2
0.1
0.2
Pigeon pea stalks
0.7
Rapeseed meal
5.5
2.5
1.5
1.0
Peanut shells
1.3
0.1
0.6
1.4
Peanut stems
0.7
0.1
0.6
0.5
Rice husk
0.5
0.5
0.1
Rice bran
2.0
1.9
1.3
Rice straw
0.7
0.1
1.0
0.3
Sawdust, rotted
0.2
Sawdust, fresh
0.1
Soot
5.5
1.0
0.4
Soybean meal
7.0
1.5
2.5
0.5
Soybean stems
1.4
0.1
1.0
0.9
Sugar cane trash
0.3
Tobacco stems
6.0
Dried water hya2.2
0.3
3.9
2.0
cinths
Weeds
0.5
0.2
0.7
0.5
Green manures(dried)Clover
2.4
0.2
0.9
2.0
Crotalaria juncea
2.0
0.2
1.0
0.8
Sesbania seban
2.1
0.2
1.1
0.8
Source of this table: Minnich, J., et al. 1979, Rodale Guide of Composting.

Appendix 1: Composition of organic materials

C/N ratio

15

300

45
20

70

70

100
200
500

150
23

61

Further reading
Agromisa, Agrodok no 2: Soil fertility management. 2001.
Agromisa, Agrodok no 11: Erosion control in the tropics. 2002.
Agromisa, Agrodok 13: Water harvesting and soil moisture retention. 2001.
Agromisa, Agrodok 21: On-farm fish culture. 1998.
Available from Agromisa, Wageningen, The Netherlands
The address you find inside on the inside of the front cover.
Attfield, H.H.D. Composting Privy. 1978, 12 pp., Technical Bulletin
7 VITA, USA.
Barnjee, R.K. & Srinivasan, K.V., Composted urban refuse andprimary sewage sludge as a fish pond manure. Agricultural Wastes
7, no. 4, 1983, pp. 209-219.
Dalpado, V.E., Mimeographed information describing compost
making from city refuse, aquatic weeds and other materials available in developing countries. 1976.
Drechsel, P., Kunze, D., Waste composting for urban and periurban agriculture: Closing the rural -urban nutrient cycle in subsaharan africa. 2001, 229 pp., CABI. ISBN: 08 51 99 5489.
Edwards, P., A review of recycling organic wastes into fish withemphasis on the tropics. Aquaculture 21, 1980. pp. 261-297.
Encyclopedia of Organic Farming, Rodale Press.
FAO, Soil management: Compost production and use in tropicaland sub-tropical environments. FAO soils bulletin 56, 1987, 177pp., FAO, Rome, Italy.
Gopal, B.R.I.J., Waterhyacinth as mulch, waterhyacinth as compost. 1987, pp. 272-275. Waterhyacinth, Amsterdam, Elsevier.
t Hart, D., Pluimers, J., Wasted Agriculture. The use of compost in
urban agriculture. 1996, 100 pp., Waste, UWEP Programme.
62

The preparation and use of compost

HDRA, Composting in the tropics I + II, 1998, Henry Doubleday
Research Association, Coventry, UK.
Hsieh, S.H., Hsieh, C.F., The use of organic matter in crop production. No. 315, ASPAC.
Jenkins, J.C., The Humanure handbook: a guide to composting
human manure. 1994, 198 pp., Jenkins Publishing. ISBN: 09644258-4-x.
Lindsey, K., Hirt, H., Use water hyacinth! A practical handbook ofuses fir the water hyacinth from across the world. 1999, Germany.
Minnich, J., Hunt, M., & editors of Organic Gardening magazine, The
Rodale guide to composting. 1979, USA.
Muller-Samann, K.M., Kotschi, J., Sustaining Growth: Soil fertility
management in tropical smallholdings. 1994, 486 pp., ICTA; GTZ.
Transl.: Christine Ernsting and Simon Chaterj, Margraf, Weikersheim,
Germany.
National Academy of Sciences, National Research Council. Making
aquatic weeds useful: some perspectives for developing countries.
Washington DC, USA.
Ngeze, P.B., Learn how to make and use compost manure in farming. 1998, 45 pp., Stantex Publishers. ISBN: 9966-917-04-7.
Njoroge J.W., Field notes on organic farming, 1994, KIOF, Nairobi,
Kenya.
Suval, H.I., Gunnerson, C.G.., Julius, D.S., Night soil composting;Appropriate Technology for water Supply and Sanitation. 1981, 81
pp., World Bank.
Roulac, J., Backyard composting. 1996, 96 pp., Devon, Green Earth
Books. ISBN: 1900322048.
Tyler, R.W., Winning the organic game. The compost marketer's
handbook. 1996, 269 pp., Alexandria, ASHS Press. ISBN:096150272X.
Further reading63

Useful addresses
Henry Doubleday Research Association (HDRA)
Ryton Organic Gardens
Coventry CV8 3LG, UK
Tel: +44 (0)24 7630 3517
Fax: +44 (0)24 7663 9229
E-mail: enquiry@hdra.org.uk; Website: http://www.hdra.org.uk

HDRA is the leading organisation promoting, researching and demonstrating organic horticulture and agriculture in the United Kingdom
and overseas. HDRA’s programme provides a question and answer
service on organic agriculture and agroforestry for NGO’s, self-helpgroups, schools and other organisations in the tropics and sub-tropics.
Requests for information should be directed to the Overseas Advisory
Section at the address given above.
Kenya Institute of Organic Farming (KIOF)
P.O. Box 34972
Nairobi, Kenya
Tel: +254 (2) 583383 / 583194
Fax: +254 (2) 583570
E-mail: kiof@iconnect.co.ke

KIOF was established in 1986 to encourage sustainable methods ofagriculture, mainly among smallholder farmers. The initial programme
was farmers’ training and extension carried out in the central districtsof Kenya. The programme has been extended with the following:? Creating awareness and providing practical training in organic
farming to farmers.
? On-farm trials and data gathering in organic farming in medium andhigh potential areas in Kenya.
? Gathering and disseminating information on organic farming
throughout Eastern Africa.
? Stimulating formation of organizations and networks on organic
farming.

64

The preparation and use of compostComposting in a barrel:
IFR/IFRA
Sidiki Gabriel Dembélé
IFR/IFRA, Katibougou, BP 06, Koulikoro, Mali
Fax: +233 26 2003
Bokashi: Addresses of institutes
Europa:Agriton, Mauritsweg 44, 8391 KC Noordwolde, The Netherlands.
Tel.: 0031 561 433115; Fax 0031 561 432677
E-mail: agriton@tref.nl; Website: www.agriton.nl
Japan:
EMRO Research Organization Inc. Takamiyagi Bldg., 2-9-2 Ginowancity, Okinawa, Japan 901-2214.
Tel.: 0081 98 890 1111; Fax 0081 98 890 1122
Asia:
APNAN Asian Pacific Natural Agricultural Network, Room A-304,
Monririn Bldg. 60/1 Soi Salom, Phaholyothin Road, Phayathai, Bangkok 10400, Thailand.
Tel.: 00 66 2 272 7126; Fax: 00 66 2 272 7127
E-mail: emro@ksc.th.com
Africa:Dr. J.F. Prinsloo, Aquaculture Research Unit, University of the North,
Private Bag X1106, Sovenga 0727, South Africa.
Fax: 0027 15 268 2294
Australia:
Dr Tony oh-ishi, EMRO Australia, 97 Dimboola Road, Horsham, Victoria 3400, Australia.
Fax: 00 61 3 53 823155
United States:
EM Technologies Inc., 3844 Karen Avenue, Long Beach, CA 908082328 USA
Contact person: Mr Glenn Kozawa
Fax: 00 1 562 421 9194

Useful addresses

65