Home composting bins
Practical Action
Balance substrate is required for optimum growth of the micro-organisms. One material
alone is sometimes not good substrate for composting and it can overcome by mixing
different substrate which is rich in different components (e.g. dry garden waste with
kitchen waste). Kitchen waste alone provides good substrate for fly breeding and it can
minimize by covering a thin layer of dry garden waste.
Mixing or ‘turning’ the composting material from time to time will aerate and help
composting material break down faster (and also prevent unpleasant odour). The compost
must be turned at least once a week.
Microorganisms in active composting stages produce lot of heat. Therefore, temperature
can reach over 60°C in the centre of a bin. This heat is desirable, as it helps to kill weed
seeds, pathogens and to break down the materials. Placing the compost bin in a sunny
location will also help the compost inside to heat up and decompose faster.
The lid of the composting bin has to be secured to prevent pests getting in. When pests
such as ants and cockroaches enter the bin will also indicate that the material in the bin
is too dry.
Troubleshooting
Table: 2 Common problems, causes and solutions for composting bin users
Problems
Possible Causes
Solution
Materials in the
bin not
decomposing or
not heating up at
all.
Not enough
nitrogen
Not enough
oxygen
Not enough
moisture
Make sure you have enough nitrogen rich
sources like manure, grass clippings or
food scraps.
Mix up the materials in the bin, so that it
can breathe.
Add some water to the bin and make sure
there is enough moisture for composting
process.
Matted leaves or
grass clippings
are not
decomposing.
Poor aeration
Lack of moisture.
Avoid adding thick layers of same
material. Use of one substrate alone does
not provide balance nutrients for
microbes. Eg. Leaves, paper, grass
clippings. Therefore, shred and mixe such
material with other material to help
composting easy and faster. Break up the
layers and mix the materials in the bin.
Stinks like rancid
butter, vinegar or
rotten eggs.
Not enough
oxygen,
Bin is too wet, or
compacted.
Mix up the bin for aeration so that it can
breathe.
Add course dry materials like straw, hay
or leaves to soak excess moisture. Add
dry materials and mix well, if it creates an
unpleasant odour.
Vermin problem
(fly larvae)
Inappropriate
materials like
meat, dairy
products
Bin is too wet
Poor aeration
Adjust the moisture by adding dry
materials or ash.
Locate the bin in a sunny place. Heat
helps to destroy fly larvae, weed seeds
and other pathogens.
Switch to a fly-proof closed bin with
enough aeration.
Odour like
ammonia.
Not enough
carbon.
Add brown materials like dried leaves,
straw, hay, shredded paper, etc.
5