Introduction

Solid wastes are waste generated from human and animal , that are normally solid and are

of no use. Waste mat be organic or inorganic. Bangalore generate about 3000 tones of waste

, out of which 70% waste are organic in nature.

Aristotle called worms the “intestines of the earth” and

stated that there may not be any other creature that has played so important a role in the

history of life on earth.

Earthworms constitute a large part of biomass (living bodies) inhabiting soil. In recent years

efforts have been made to use the potential of earthworms in recycling of nutrients, waste

management and development of vermicomposting systems at commercial scale .These are

also called as “Ecosystem engineers” as they increase the numbers and types of microbes in

the soil by creating conditions under which these creatures can thrive and multiply. The

objective of this article is to present an overview of the vermicomposting technology.

In India, the integration of crops and livestock and use of manure as fertilizer were

traditionally the basis of farming systems. But development of chemical fertilizerindustry

during the green revolution period created opportunities for low-cost supply of plant

nutrients in inorganic forms which lead to rapid displacement of organic manures derived

from livestock excreta. The deterioration of soil fertility through loss of nutrient sand

organic matter, erosion and salinity, and pollution of environment are the negative

consequences of modern agricultural practices. In India, millions of tons of live stock excreta

are produced annually. Odour and pollution problems are of concern .

Currently the fertilizer values of animal dung are not being fully utilized resulting in loss of

potential nutrients returning to agricultural systems. The potential benefits of

vermicomposting of livestock excreta include control of pollution and production of a value

added product. Vermicomposting of different livestock excreta including cattle dung; horse

waste; pig waste; goat waste; sheep waste; turkey waste and poultry droppings has been

reported. Organic wastes can be ingested by earthworms and egestedas a peat-like material

termed “vermicompost”.

Abstract Vermicompost is the product or process of composting using various worms, usually red

wigglers, white worms, and other earthworms to create aheter ogeneous mixture of

decomposing vegetable or food waste, bedding materials, and vermicast. Vermicast, also

called worm castings, worm humus or worm manure, is the end-product of the breakdown

of organic matter by an earthworm. These castings have been shown to contain reduced

levels of contaminants and a higher saturation of nutrients than do organic materials before

vermicomposting. Containing water-soluble nutrients, vermicompost is an excellent,

nutrient-rich organic fertilizer and soil conditioner. This process of producing vermicompost

is called vermicomposting

The Difference between Vermiculture and Vermicomposting

Vermiculture is the culture of earthworms. The goal is to continually increase the number of

worms in order to obtain a sustainable harvest. The worms are either used to expand a

vermicomposting operation or sold to customers who use them for the same or other

purposes (see “On-Farm Vermiculture” later in this manual).

Vermicomposting is the process by which worms are used to convert organic materials

(usually wastes) into a humus-like material known as vermicompost. The goal is to process

the material as quickly and efficiently as possible.

These two processes are similar but different. If your goal is to produce vermicompost, you

will want to have your maximum worm population density all of the time. If your goal is to

produce worms, you will want to keep the population density low enough that reproductive

rates are optimized. Both of these processes will be described in some detail in this manual.

Vermicomposting materials

Decomposable organic wastes such as animal excreta, kitchen waste, farm residue sand

forest litter are commonly used as composting materials. In general, animal dung mostly

cow dung and dried chopped crop residues are the key raw materials. Mixture of

leguminous and non-leguminous crop residues enriches the quality of vermicompost.

.

(earthworm)

DIFFERENT TYPE OF EARTHWORMS

There are different species of earthworms viz. Eisenia foetida (Red earthworm),Eudrilus

eugeniae (night crawler), Perionyx excavatus etc. Red earthworm is preferred because of its

high multiplication rate and thereby converts the organic matter into vermicompost within

45-50 days. Since it is a surface feeder it converts organic materials into vermicompost from

top

Important characteristics of red earthworm (Eisenia foetida)

Characters Eisenia foetida

Body length 3-10cm

Body weight 0.4-0.6g

Maturity 50-55days

Conversion rate 2.0 q/1500worms/2 months

Cocoon production 1 in every 3 days

Incubation of cocoon 20-23days

Anecic (Greek for “out of the earth”) – these are burrowing worms that come to the surface

at night to drag food down into their permanent burrows deep within the mineral layers of

the soil. Example: the Canadian Night crawler

Endogeic (Greek for “within the earth”) – these are also burrowing worms but their

burrows are typically more shallow and they feed on the organic matter already in the soil,

so they come to the surface only rarely.

Epigeic (Greek for “upon the earth”) – these worms live in the surface litter and feed on

decaying organic matter. They do not have permanent burrows. These “decomposers” are

the type of worm used in vermicomposting.

Why should an organic farmer be interested in vermiculture

and/or vermicomposting?

Vermicompost appears to be generally superior to conventionally produced compost

in a number of important ways;

Vermicompost is superior to most composts as an in oculant in the production of

compost teas;

Worms have a number of other possible uses on farms, including value as a high-

quality animal feed;

Vermicomposting and vermiculture offer potential to organic farmers as sources of

supplemental income

It can be quicker, but to make it so generally requires more labour;

It requires more space because worms are surface feeders and won’t operate in

material more than a meter in depth;

It is more vulnerable to environmental pressures, such as freezing conditions and

drought;

Perhaps most importantly, it requires more start-up resources, either in cash (to buy

the worms) or in time and labour (to grow them).

It is a stable and enriched soil conditioner.

It helps in reducing population of pathogenic microbes.

It helps in reducing the toxicity of heavy metals

Types of vermicomposting

The types of vermicomposting depend upon the amount of producton and composting

structures.

Small-scale vermicomposting is done to meet the personal requirement and farmer can

harvest 5-10 tonnes of vermicompost annually.

While, large-scale vermicomposting is done at commercial scale by recycling large quantity

of organic waste with the production of more than 50 – 100 tonnes annually.

Methods of vermicomposting

Vermicromposting is done by various methods, among them bed and pit methods are more

common.

Bed method: Composting is done on the pucca / kachcha floor by making bed(6x2x2 feet

size) of organic mixture. This method is easy to maintain and to practice

Pit method: Composting is done in the cemented pits of size 5x5x3 feet. The unit is covered

with thatch grass or any other locally available materials. This method is not preferred due

to poor aeration, water logging at bottom, and more cost of production.

BED METHOD PIT METHOD

Process of vermicomposting

Following steps are followed for vermicompost

1. Preparation Vermicomposting unit should be in a cool, moist and shady site Cow

dung and chopped dried leafy materials are mixed in the proportion of3:1and are

kept for partial decomposition for 15 – 20 days.

2. A layer of 15-20cm of chopped dried leaves/grasses should be kept as bedding

material at the bottom of the bed.

3. Beds of partially decomposed material of size 6x2x2 feet should be made Each bed

should contain 1.5-2.0q of raw material and the number of beds can be increased as

per raw material availability and requirement.

4. Red earthworm (1500-2000) should be released on the upper layer of bed

5. Water should be sprinkled with can immediately after the release of worms Beds

should be kept moist by sprinkling of water (daily) and by covering with gunny

bags/polythene.

6. Bed should be turned once after 30 days for maintaining aeration and for proper

decomposition.

7. Compost gets ready in 45-50 days

8. The finished product is 3/4th of the raw materials used.

Preventive measures

The floor of the unit should be compact to prevent earthworms migration into the

soil.

15-20 days old cow dung should be used to avoid excess heat.

The organic wastes should be free from plastics, chemicals, pesticides and

metals etc.

Aeration should be maintained for proper growth and multiplication of

earthworms.

Optimum moisture level (30-40 %) should be maintained 18-25oC temperature

should be maintained for proper decomposition.

Nutrient content of vermicompost The level of nutrients in compost depends upon the source of the raw material and the

species of earthworm. A fine worm cast is rich in N P K besides other nutrients .Nutrients in

vermicompost are in readily available form and are released within a month of application.

Nutrient Analysis of Vermicompost Parameters Content

pH 6.8

OC% 11.88

OM% 20.46

C/N ration 11.64

Total Nitrogen (%) 1.02

Available N (%) 0.50

Available P (%) 0.30

Available K (%) 0.24

Ca (%) 0.17

Mg (%) 0.06

Advantages

There are many advantages of vermicompost :

It provides efficient conversion of organic wastes/crop/animal residues.

It is a stable and enriched soil conditioner.

It helps in reducing population of pathogenic microbes.

It helps in reducing the toxicity of heavy metals.

It is economically viable and environmentally safe nutrient supplement for

organic food production.

It is an easily adoptable low cost technology

Doses The doses of vermicompost application depend upon the type of crop grown in the

field/nursery. For fruit crops, it is applied in the tree basin. It is added in the pot mixture for

potted ornamental plants and for raising seedlings. Vermicompost should be used as a

component of integrated nutrient supply system.

Crops Dose/rate

Field crops 5-6t/ha

Fruit crops 3-5kg/plant

Pots 100-200g/pot

FACTOR THAT SHOULD BE TAKEN CARE OF

Effect of Temperature on Vermicomposting:

The temperature range selected for experiment was 15, 20, 25, 30, 35 and 40Oc taking into

account average minimum and maximum temperatures found in the Sangli area and in the

seasonal variations in the year. For every temperature selected, the three plastic tubs / pots

were use dand were incubated for five weeks in BOD incubators and biomass weight of

earthworm pot sand cocoons count was taken as above.

Effect of pH of Material on the Vermicomposting:

The PH of vermicomposting material was adjusted with 1 N HCL / 1 N NaOH to

2,3,4,5,6,7,8,9 and 10.The pH values adjusted materials were filled in 2kgamount in three

pots (in triplicate) and inoculated with two earthworms per pot and incubated in dark at

25Oc for five weeks. The average bio massof worms and cocoon count / pot was taken per

week as above.

Effect of Particle size of Vermicomposting:

(PH of material was adjusted to 7) The particle size range of material selected for

experiment was 0.5 - 1mm, 110 mm, 10-20 mm and material of each particle size was filled

in three pots in 2 kg amounts (intriplicate) and inoculated with two earthworms /pot and

incubated at 25OC for five weeks in dark .The average biomass of worms and cocoon count

pot was taken per week as above.

Effect of Moisture Content of Material on the Vermicomposting:

(pH of material was adjusted to 7.0 and 1size). The moisture contents of vermicomposting

material was adjusted to 50,60,70,80 and 90 %with water and filled in 2 kg amounts in three

pots in triplicate) and inoculated with two earthworms/ pot and incubated at 25Oc in dark

for five weeks .The average biomass of worms and cocoon count /pot was taken per week

as above.

Aerobic condition :

Aerobic condition should be there .

Benefits from vermicomposting

Soil

Improves soil aeration

Enriches soil with micro-organisms (adding enzymes such as phosphatase and cellulase)

Microbial activity in worm castings is 10 to 20 times higher than in the soil and organic

matter that the worm ingests

Attracts deep-burrowing earthworms already present in the soil

Improves water holding capacity

Plant growth

Enhances germination, plant growth, and crop yield

Improves root growth and structure

Enriches soil with micro-organisms (adding plant hormones such

as auxins and gibberellic acid)

Economic

Bio-wastes conversion reduces waste flow to landfills

Elimination of bio-wastes from the waste stream reduces contamination of other

recyclables collected in a single bin (a common problem in communities

practicing single-stream recycling)

Creates low-skill jobs at local level

Low capital investment and relatively simple technologies make vermicomposting

practical for less-developed agricultural regions

Environmental

Helps to close the "metabolic gap" through recycling waste on-site

Large systems often use temperature control and mechanized harvesting, however

other equipment is relatively simple and does not wear out quickly production

reduces greenhouse gas emissions such as methane and nitric oxide (produced in

landfills or incinerators when not composted or through methane harvest)

As Fertilizer

Vermicompost can be mixed directly into the soil, or steeped in water and made into

a worm tea by mixing some vermicompost in water, bubbling in oxygen with a small

air pump, and steeping for a number of hours or days.

The microbial activity of the compost is greater if it is aerated during this period. The

resulting liquid is used as a fertilizer or sprayed on the plants.

The dark brown waste liquid, or leachate , that drains into the bottom of some

vermicomposting systems as water-rich foods break down, is best applied back to the bin

when added moisture is needed due to the possibility of phytotoxin content and organic

acids that may be toxic to plants.

The pH, nutrient, and microbial content of these fertilizers vary upon the inputs fed to

worms. Pulverized limestone, or calcium carbonate can be added to the system to raise the

pH.

Troubleshooting

Smells

When closed, a well-maintained bin is odourless; when opened, it should have little smell - if

any, the smell is earthy. Worms require gaseous oxygen. Oxygen can be provided by air

holes in the bin, occasional stirring of bin contents, and removal of some bin contents if they

become too deep or too wet. If decomposition becomes anaerobic from excess feedstock

added to the bin in wet conditions, or layers of food waste have become too deep, the bin

will begin to smell like ammonia.

Moisture

If decomposition has become anaerobic, to restore healthy conditions and prevent the

worms from dying, the smelly, excess waste water must be removed and the bin returned to

a normal moisture level. To do this, first reduce addition of food scraps with a high moisture

content and second, add fresh, dry bedding such as shredded newspaper to your bin, mixing

it in well.

Pest species

Pests such as rodents and flies are attracted by certain materials and odours, usually from

large amounts of kitchen waste, particularly meat. Eliminating the use of meat or dairy

product in a worm bin decreases the possibility of pests.

In warm weather, fruit and vinegar flies breed in the bins if fruit and vegetable waste is not

thoroughly covered with bedding. This problem can be avoided by thoroughly covering the

waste by at least 2 inches of bedding. Maintaining the correct pH (close to neutral) and

water content of the bin (just enough water where squeezed bedding drips a couple of

drops) can help avoid these pests as well.

Worms escaping

Having worms escape is one of the most feared outcomes for many new vermicomposters.

Worms generally stay in the bin, but may try to leave the bin when first introduced, or often

after a rainstorm when outside humidity is high. Maintaining adequate conditions in the

worm bin and putting a light over the bin when first introducing worms should eliminate

this problem.

Nutrient levels

Commercial vermicomposters test, and may amend their products to produce consistent

quality and results. Because the small-scale and home systems use a varied mix of feed

stocks, the nitrogen, potassium and phosphorus content of the resulting vermicompost will

also be inconsistent. NPK testing may be helpful before the vermicompost or tea is applied

to the garden. In order to avoid over-fertilization issues, such as nitrogen burn,

vermicompost can be diluted as a tea 50:50 with water, or as a solid can be mixed in 50:50

with potting soil. The mucus produced creates a natural time release fertilizer which cannot

burn plants.

Pests and Disease of worms

Compost worms are not subject to diseases caused by micro-organisms, but they are subject

to predation by certain animals and insects (red mites are the worst) and to a disease known

as “sour crop” caused by environmental conditions. The following is a brief overview of the

most common pests and diseases likely to be experienced in Canada.

• Moles. Earthworms are moles’ natural food, so if a mole gets access to your worm

bed, you can lose a lot of worms very quickly (Gaddie, op. cit.). This is usually only a

problem when using windrows or other open-air systems in fields. It can be

prevented by putting some form of barrier, such as wire mesh, paving, or a good

layer of clay, under the windrow.

• Birds. They are not usually a major problem, but if they discover your beds they will

come around regularly and help themselves to some of your workforce. Putting a

windrow cover of some type over the material will eliminate this problem. These

covers are also useful for retaining moisture and preventing too much leaching

during rainfall events. Old carpet can be used for this purpose and is very effective.

• Centipedes. These insects eat compost worms and their cocoons. Fortunately, they

do not seem to multiply to a great extent within worm beds or windrows, so damage

is usually light. If they do become a problem, one method suggested for reducing

their numbers is to heavily wet (but not quite flood) the worm beds. The water

forces centipedes and other insect pests (but not the worms) to the surface, where

they can be destroyed by means of a hand-held propane torch or something similar

(Gaddie, op. cit.; Sherman, 1997).

• Ants. These insects are more of a problem because they consume the feed meant for

the worms (Myers, 1969). Ants are particularly attracted to sugar, so avoiding sweet

feeds in the worm beds reduces this problem to a minor one. Keeping the bedding

above pH 7 also helps (see mites and sour crop below).

• Mites. There are a number of different types of mites that appear in vermiculture and

vermicomposting operations, but only one type is a serious problem: red mites.

White and brown mites compete with worms for food and can thus have some

economic impact, but red mites are parasitic on earthworms. They suck blood or

body fluid from worms and they can also suck fluid from cocoons (Sherman, 1997).

The best prevention for red mites is to make sure that the pH stays at neutral or

above. This can be done by keeping the moisture levels below 85% and through

the addition of calcium carbonate, as required.

• Sour crop or protein poisoning. This “disease” is actually the result of too

much protein in the bedding. This happens when the worms are overfed. Protein

builds up in the bedding and produces acids and gases as it decays (Gaddie, op. cit.).

According to Ruth Myers (1969): “when you see a worm with a swollen clitellum13 or

see one crawling aimlessly around on top of the bedding, you can just bet on sour

crop and act accordingly, but fast”. Her recommended solution is a “massive dose of

one of the mycins, such as farmers give to chicken or cattle”. Farmers wishing to

avoid these or similar antibiotics should work to prevent sour crop by not

overfeeding and by monitoring and adjusting pH on a regular basis. Keeping the pH

at neutral or above will preclude the need for these measures

Conclusion

Vermicomposting is more than just composting with worms. It’s a way to help cut down on

methane gases (greenhouse gases), its eco-friendly and produces one of the most nutrient

enriched fertilizers around. It’s cheap and low maintenance to produce. Most important it’s

one more way to make our tomorrow a little greener. Vermicompost or worm fertilizer is

strictly organic. Vermicompost is used as an organic fertilizer in agricultural gardens.

Vermicompost enriches the soil, creates an ecologically safe system of food production, and

raises land productivity. By using vermicompost in gardens, harmful chemicals and pesticides

are no longer needed in the cultivation of crops.

References

Sewage disposal and air pollution engineering By S K Garg Volume II

(23rd edition).

http://en.wikipedia.org/wiki/Vermicompost.

http://www.slideshare.net/JenniferHeaton/vermicomposting.

Table of Contents

1. Introduction

2. Difference between Vermiculture and Vermicomposting

3. Different type of earthworm 4. Why should an organic farmer be interested in vermiculture and/or vermicomposting

5. Types of vermicomposting

6. Process of vermicomposting

7. Preventive measures

8. Advantages

9. Factors that should be taken care of

10. Benefits from vermicomposting

11. Troubleshooting

12. Pests and Diseases of worm

13. Conclusion

14. References