Vermicomposting | Its Methods, Advantages and Disadvantages

Thus, it is called black gold and is an ideal form of natural manure that is easy to make, economical, and rich in nutrients.

Vermicompost is rich in humus, Nitrogen (2-3 %), phosphorus ( 1.55-2.25%), Potassium ( 1.85-2.25 %), micronutrients, and other beneficial soil microbes.

It increases the population of nitrogen-fixing bacteria and actinomycetes.

Overall, it is an ideal form of an organic amendment to improve crop growth and yield.

Methods of vermicomposting

• Bed method:
• Pit method

Bed method:

This is a widely used method as it is easy to handle, control, and be protected well.

Here, the bed is made on the floor with dimensions like (6×2×2 feet) or any other as per requirement.

Pit method:

This is a less practiced method as the conditions cannot be well controlled.

Here, composting is done in pits made of cement or bricks of different dimensions, like 5×5×3 feet.

There is a chance of ant or insect infestation in this method.

Materials used for Vermicomposting

• Organic waste- kitchen, animal, and farm waste ( cow dung and dried crop waste are mainly used). Always use both leguminous and non-leguminous crop waste for vermicomposting.
• Earthworms- Locally available earthworms and those found in soil show prolonged action. For quick action, specific earthworms are preferred.
• Cow dung
• Water
• Gunny bags
• Large bin (cemented or plastic tank)

The specific species of earthworms used for composting include

1. Eisenia fetida (red wriggler worms)- these are mostly preferred due to their vigorous multiplication property.
2. Eudrilluseuginiae (African nightcrawler)
3. Perionyx excavates

Process of Vermicomposting

1. To prepare the vermicompost, a plastic or concrete tank can be used according to the availability (Size- based on the number of raw materials available)
2. Collect the dried biomass ( garden waste, animal waste, municipal waste, etc.) and chop them.
3. Mix the chopped dry material with cow dung in a 1:3 ratio and keep them aside for 15-20 days for partial decomposition.
4. Add a thin layer of soil /sand (2-3 inches) at the bottom of the tank.
5. Prepare the bedding by adding the partially decomposed cow dung and dried waste mixture. Distribute it evenly on the soil.
6. Continually add the mixture up to a depth of 0.5-1 foot.
7. Now release the earthworms in the tank (1000-2000 earthworms / square meters). Cover the mixture with gunny bags/straws/ plastic.
8. Monitor the bin for the availability of food to the earthworms and add the food (fruit and vegetable peels, other kitchen waste) when necessary (make sure not to add excess food)
9. Do water regularly to maintain moisture.
10. Monitor the composting tank to maintain temperature and moisture
11. Beds should be turned in every 30 days for aeration and proper decomposition.
12. The compost will be ready in 45-50 days.

Harvesting the compost

• Earthworms eat the food and leave the excreta.

• A soft, black/brown-colored component similar to humus is formed in the bin within 45-60 days.

• This is called worm casting/ vermicast/ vermicompost and collects the casting formed on the top layer.

• Before the collection, separate the earthworms and transfer them into new biomass.

• Earthworms will start their activities and continue with the process of vermicomposting.

• The castings can be collected once a week.

Precautionary and Preventive measures

• The site should be cool, shady, and moist.
• Biomass should be properly dried.
• Cattle dung should be 15-20 days old to avoid heat.
• Organic waste should be free from plastics, pesticides, metals, chemicals, and other toxic materials.
• Avoid adding dairy, ginger, meat, and acidic foods like lemon, orange, and citrus to feed the earthworms.
• Proper aeration should be maintained for the growth and multiplication of earthworms.
• Optimum moisture should be maintained (above 50 %, usually 70-80 % is considered ideal)
• The Optimum temperature should be maintained (Temperature- 18-25^o C)

Application of vermicompost in farm

• The dosage of vermicompost is based on the crops we grow.

• For field crops, 5-6 tonnes/ ha vermicompost is applied.

• For horticultural crops, it is advised to combine an equal amount of manure with vermicompost.

• In fruit crops, apply 4-5 kg of vermicompost per plant in the tree basin. Vermicompost can also be used in potted plants.

• 100-200 gm/ pot is the ideal dose for plants grown in pots.

Other components derived from Vermicompost        

Vermiwash

• It is the excreta and mucus secretion of the earthworms.

• This can be collected by passing water through the medium of the earthworms.

• It is a pale yellowish liquid containing micronutrients from the organic matter in the medium.

• It also contains enzymes and secretions of earthworms, which aid in the growth of the plant.

Advantages of vermicompost

• Vermicompost helps improve soil structure, texture, porosity, water-holding capacity, drainage, and aeration and reduces erosion.
• It improves plant growth by enabling the growth of new shoots and leaves, thereby increasing productivity.
• It helps to neutralize the pH of the soil.
• Vermicompost enhances the soil’s microbial activity and adds beneficial microbes, lowering pest and disease incidence.
• It is easy to apply and handle, economical and has no foul odor.
• It is free from any pathogens or harmful materials.
• It contains several micro and macronutrients, vitamins, enzymes, and hormones like auxins and gibberellins.

Disadvantages of Vermicompost

• Odor- If not done correctly, it releases a foul odor. Filling the compost bin with green plants forms ammonia and produces the smell. Adding carbon sources like paper helps to neutralize the smell.
• Time- It is a time-consuming process and usually takes 2-3 months to complete the process
• Maintenance- Temperature needs to be maintained for better action by earthworms. The bad odor attracts rodents and flies. So, the bin should be adequately covered.

Frequently asked questions and answers.

1. How many worms are required for vermicomposting

Around 1000-2000 earthworms are required per square meter.

So, calculate the composting area and decide the number of earthworms required.

2. Do you need worms to compost

No! Worms are not mandatory for compost preparation. Even microbial cultures, including cattle urine, can help in better compost. You need to keep the compost material moist and covered till the process happens.

3. Where to buy vermicast fertilizer

You can buy it online from reliable vendors.

4. Do worms eat mushrooms

Worms eat almost anything organic. They eat mushrooms, and since it is a good source of nutrition, it can result in high-quality compost.

References

• Vermicomposting worms.
• Vermicomposting