Vermicomposting: what it is and how it works
Vermicomposting is a form of composting that relies on the work of earthworms
Image: One of my little wrigglers from the composter by allispossible.org.uk is licensed under CC BY 2.0
Vermicomposting is the biological process of valuing organic matter that relies on the work of earthworms, and can be considered as a type of recycling of organic waste. Vermicomposting is a type of compost that uses earthworms in addition to natural microorganisms to degrade organic matter. The process takes place faster than composting without earthworms and produces earthworm humus as a substrate. This is a nutrient-rich fertilizer that is great for plants.
Nowadays, when sustainability is gaining strength, much is discussed about the issue of the volume of waste that is generated in homes, because even separating the recyclables, we still have a lot of organic waste. However, a large part of this type of waste is made up of food scraps that can go to a composter, which is fully possible to be installed in houses or apartments). This simple procedure leads to a reduction in the amount of organic waste dumped in landfills and dumps, reducing methane gas emissions.
Home composting, in general, can take place in three ways: dry, vermicomposting or automatic. The automatic makes use of a mechanical composter, which uses patented microorganisms capable of multiplying at high temperatures, high salinity and acidity, being a simpler, more practical and sustainable way of making compost at home; drought only deals with the decomposition of food by microorganisms, and has the same principle as vermicomposting; however, in drought, worms are not added to digest organic matter.
Vermicomposting uses earthworms and can be carried out in houses and apartments using domestic composters (learn more in the article "Domestic composting: how to do it and benefits"). This technique requires little energy consumption and less time for compost production compared to dry composting, since earthworms break down organic matter, facilitating the work of microorganisms. With this technique, there is the formation of vermicompost, which is the product obtained through the action of earthworms in organic residues. Vermicompost is also known as earthworm humus and is a great organic fertilizer, very rich in bacterial flora. Basically, it's "recycled" organic matter.
In addition to being more stable, especially in terms of pH, the carbon/nitrogen ratio and the physical, chemical and biological properties capable of assisting in the good performance of crops, humus returns to the earth five times more nitrogen, twice as much calcium, twice and half as much magnesium, seven times as much phosphorus, and 11 times as much potassium.
Edited and resized image of Sippakorn yamkasikorn, is available on Unsplash
Advantages of vermicomposting
- It's not aggressive to the environment;
- Does not contaminate soil and water like chemical fertilizers;
- Enriches the soil with nutrients;
- Great source of nutrients for plants;
- Control of soil toxicity, correcting excess aluminum, iron and manganese;
- Increased plant resistance to pests and diseases;
- Greater uptake of nutrients by plant roots;
- It favors the entry of air and water circulation in the ground;
- Improves soil structure;
- Provides life in the form of micro-organisms to the soil;
- Provides production of healthier foods;
- Production of high quality fertilizer for maintenance of gardens and vegetable gardens.
- What is the trophobiosis theory
- what is agroecology
earthworms
The importance of earthworms for the fertilization and recovery of soils has been known for a long time and the philosopher Aristotle defined these beings as "earth plows", thanks to their ability to excavate the hardest terrain. This worm has the power to ingest soil and organic matter equivalent to its own weight, in addition to digesting and expelling about 60% of what it ate in the form of humus.
According to studies, the type of earthworm most suitable for vermicomposting is the detritivore, as it feeds on dead organic matter, better withstands the adversities of temperature and acidity, which occur in a decomposition process, and reproduces according to the amount of food available, that is, better for breeding in captivity.
Within this typology, the species that is commonly used is the Eisenia Andrei (Epigean species), also known as California red or organic waste earthworm. These worms are able to process a wide variety of materials in less time, promote the acceleration of compost maturation, have high activity, compost conversion rate into humus and high reproduction rate.
Escape from the worms
When the environment inside the compost bin (also called the earthworm) is unfavorable for this animal, the earthworms can flee, so it is necessary that the containers are always properly closed. In most cases, these bad conditions lead to the loss of reproductive activity or death of the worms. For this not to happen, pay attention to some parameters such as:
- Humidity: lack of water or low humidity reduces the action of microorganisms and earthworms can die from dehydration; and if the environment is full of water, this can also lead to the death of worms, interfere with air circulation and give off a bad smell (see more in the article "Moisture in compost bin: very important factor in composting");
- Porosity/sanding: if the substrate has high density and compaction, there may be a lack of spaces and a low percentage of oxygen, affecting the activity of the earthworms;
- Nature of the residues: some residues end up raising the temperature, acidity levels and taking a long time to decompose, affecting the environment of the earthworms (see the article "What can you put in the compost bin?" what not to put in your compost bin and how to insert the compost bins residues in the article "Feeding earthworms in the compost bin: how to correctly introduce residues");
- C/N ratio: residues have variable amounts of Carbon and Nitrogen, which are essential for living beings - high nitrogen and low carbon ratios interfere with the action of microorganisms and bring unfavorable conditions to earthworms (read the article " Learn how to balance the relationship between carbon and nitrogen in your compost" to better understand);
- pH: earthworms need an environment with a pH between 5 and 8, outside this range, their activity may decrease (see further details in the article "What is the influence of pH on compost?");
- Temperature: earthworm metabolism is low at temperatures below 15°C; colder than that they die; and at high temperatures, too (learn more in the article "Basic conditions for composter maintenance: temperature and humidity").
| Problem | Cause | Solution |
|---|---|---|
| Earthworms accumulate in the upper layers of the earthworm or very wet bed | excess water | Renew the bedding, add more sawdust and do not add water-rich foods |
| Earthworms accumulate at the bottom of the earthworm or very dry bed (no water comes out when squeezing the compost) | Lack of water | spray the bed with water |
| unpleasant odors | Bed not too airy, too much food | Stop adding food, stir the bed well and do not add any food |
| Earthworms start to eat the humus | Little food or bed needs to be changed | add food and change beds |
| Excess residue or presence of flies | Adding excess food | Stop adding food and stir material |
| musty smell | Difficult foods to compost like meat, fish, dairy products and fats. | Do not put these foods in the composter |
| Appearance of flies | Slow decomposition acidic environment | Place assorted foods cut into pieces. Do not deposit acidic fruits |
Compost or earthworm
In the case of homemade vermicomposting, the domestic composter or earthworm is the place where the worms will act to "recycle" the organic waste. Basically, the device consists of three or more stackable plastic boxes, but that depends on the demand of people in the house.
The first two boxes are digesters. The first (from above), where waste is deposited, needs a lid and has holes at the bottom; the latter serves as a collector to store the organic slurry produced.
Composting is a simple and hygienic process to recycle the organic waste we produce at home, however, there are some precautions that must be taken to avoid bad odors, attraction of animals and death of earthworms.
It is therefore recommended, as a step-by-step, that the residues are successively deposited in rows (preferably chopped) and then in layers, always preserving on the opposite side a layer of ready compost, residue-free humus which will serve for what is called a "bed". The “bed” is like a place of safety, where the worms feel comfortable, and must exist in both digestive boxes. They will migrate through all the boxes, going up and down, always using the holes.
To purchase a composter, go to the virtual store and choose the best type for your family.
