How to Use a Compost Bin
1. Correct Locating of the bin
Bins should be located on a suitable place of the garden with convenient distance from the kitchen (5 – 15 m) .This place should not be a water logged area during the rainy season and a good basement is required for a steady installation. The basement should allow the drainage of excess water and it should permit the entry of soil microorganisms, earthworms etc. It is important to ensure that rats or any other pests should not enter tot the bin. It is best that the bin is placed in a sunny area to enable better composting in high temperatures (Thermophlic composting).
2. Adding the materials for composting & maintenance
- Fill the bin with household organic waste as alternative layers of kitchen waste and dried garden waste. Do not add inorganic (polythene, plastic, glass, metal) or slow degradable materials like coconut husk, coconuts shells, banana stalk etc. (table:1)
- some twigs and branches can be shredded into smaller pieces so that it accelerate the composting process
- Do not add any problematic materials like meat scraps, fish, dairy products and oily products to the bin (this attract pest). Smaller quantities of above waste can burry in the center of bin to minimize pest attraction and malfunctions. Further, good monitoring mechanisms are needed to optimize the composting process.
- A minimum volume of material is required to activate composting and therefore, the compost bin must be at least ¾ full for the process to work well.
- Composting cannot occur without moisture and therefore, spray some water to moist the dry materials in a bin. Too much moisture creates anaerobic conditions that can create unpleasant odors (moist but should not squeeze out water from the bin).
- 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 odor). 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 center 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.
Table 2: Common problems, causes and solutions for composting bin users
|Materials in the
not heating up at
|Make sure you have enough nitrogen rich
sources like manure, grass clippings or
Mix up the materials in the bin, so that it
Add some water to the bin and make sure
there is enough moisture for composting
|Matted leaves or
|Poor aeration or
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 mixed 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
Bin is too wet, or
|Mix up the bin for aeration so that it can
Add course dry materials like straw, hay
or leaves to soak excess moisture. Add
dry materials and mix well, if it creates an
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
|Not enough carbon.
||Add brown materials like dried leaves,
straw, hay, shredded paper, etc.
flies, or other
crows, dogs etc.)
meat, oil, bones),
Material like fresh
food is too close to
the surface of the
|Do not add inappropriate materials to a
compost bin (large scale).
Switch to a rodent-proof safe bin.
|This is normal in composting and part of the natural
|Sometimes become a problem. Use
proper bin design which can keep away
from household pest like cockroaches,
Table: 3. Advantages and disadvantages of composting bins
- Management practices are easy since it eliminates external weather conditions.
- Minimum animal/pest attractions due to safe bin designs.
- Improve hygiene conditions of the surrounding environment.
- Takes less space in the garden.
- The unit is movable and can locate on any place in the garden
- Aesthetically good looking
- High cost for purchasing(Rs. 1000/- to 2500/-)
- Improper/poor designs create problems and therefore it can discourage bin users.
- Need proper maintenance ( if proper moisture level is not maintained unpleasant odor, and vermin problems will occur)
- Some poor designs stops contribution of soil micro-organisms and earthworms to the degradation process.