Bokashi and vermicomposting are different methods for transforming complex organic matter like food waste into a nutrient-rich soil amendment with an abundance of beneficial soil microbes. Though similar in purpose, bokashi and vermicomposting involve vastly different processes and create unique products.
Bokashi ferments organic matter using anaerobic bacteria and yeasts. It produces partially-decomposed organic matter.
Vermicomposting is an aerobic decomposition process involving earthworms and mesophilic bacteria. It produces stable, decomposed organic matter and worm castings.
Bokashi and vermicomposting are exceedingly effective methods for turning food waste and other organic materials into resources that enrich the soil and promote healthy, vigorous plant growth. However, there are fundamental differences between these two methods. Let’s explore the differences between bokashi and vermicomposting in more detail.
Quick Reference Guide
The following table summarizes the differences between bokashi and vermicomposting:
|Anaerobic fermentation (digestion) process performed by anaerobic bacteria, mainly lactic acid bacteria and yeasts
|Aerobic decomposition process performed by earthworms and mesophilic bacteria
|Knowledge and effort (labor) required
|Minimal knowledge or physical labor is necessary.
|Technical knowledge is necessary for:
– Setting up and maintaining vermicomposting systems
– Providing optimum environmental conditions for the worms
– Harvesting vermicompost and castings
|Types of food waste
|Any type of food waste
|Meat and dairy are excluded.
Foods that are oily, acidic, or pungent are also excluded.
|Four to six weeks
|Stability of finished product
|Pre-decomposed (pickled), highly acidic organic matter that must be mixed in soil or compost for two to three weeks so the bokashi material can decompose and mature
|Stable, decomposed organic matter and worm castings that can be used immediately
|Content of finished product
|Bokashi compost is rich in plant nutrients and beneficial bacteria and yeasts.
|Vermicompost has a wealth of plant nutrients and beneficial rhizospheric bacteria.
|Minimal space is necessary.
Most of the bokashi process can be undertaken indoors, but the last stage requires an outdoor area.
|Minimal space is necessary.
The entire vermicomposting process can be undertaken indoors or outdoors.
|Inoculated substrate and a container with a tap fixture
|A container or worm bin with a tap fixture
Bedding materials such as cardboard, leaves, or coco coir
Comparing the Two Methods
Bokashi uses anaerobic processes to create a fermented organic pre-compost that needs further processing before it can be used.
Vermicomposting uses aerobic decomposition to create a stable compost that can be used immediately. However, it takes more materials, knowledge, and effort than bokashi.
Processes and Microorganisms Involved
The processes involved in bokashi and vermicomposting have significant differences.
Bokashi is an anaerobic digestion or fermentation process performed by anaerobic microorganisms. Organic materials like food waste are added to an airtight container with carbohydrate-rich material (such as wheat bran) inoculated with anaerobic bacteria and yeasts.
These microbes use enzymes to digest the carbohydrates in organic matter, creating acidic conditions that prevent the organic materials from being decomposed by other kinds of microbes. As a result, the organic matter is fermented rather than decomposed.
In contrast, vermicomposting is an aerobic decomposition process involving earthworms and aerobic bacteria. Food wastes and other kinds of organic matter are placed inside worm bins, where worms consume them and physically break down into smaller particles.
After the worms have performed the physical stage of the decomposition process, the organic matter passes into their intestines, where it is fully decomposed by mesophilic bacteria through biochemical means. Neutral pH conditions prevail throughout the vermicomposting process.
The distinct processes involved in bokashi and vermicomposting create vastly different final products.
The bokashi method produces fermented or pickled organic material rather than decomposed matter. Bokashi material is a type of pre-compost that has been anaerobically digested but retains its physical form and nutritional content.
The initial product is highly acidic and must be mixed with soil or added to a compost pile for a brief aerobic decomposition process. After the fermented bokashi material has decomposed, it provides a nutrient-rich soil amendment with a rich diversity of beneficial soil micro-organisms.
Vermicomposting produces a mixture of decomposed organic matter and worm castings (feces) called vermicompost. The organic matter in the vermicompost mixture is decomposed into a simple, stabilized form that can be used immediately as a soil amendment.
Vermicompost has a light, soft texture. The worm castings are the most valuable part of vermicompost and contain high amounts of essential plant nutrients. Castings also contain beneficial soil bacteria that perform crucial plant functions like producing plant growth hormones and suppressing fungal pathogens.
Space and Material Requirements
Minimal space is necessary to practice bokashi and vermicomposting. Both methods can be performed indoors, though bokashi requires a final decomposition step that must be done outdoors.
The materials and items used in bokashi and vermicomposting also differ. Vermicomposting requires a container with a tap (to drain excess liquids), earthworms, bedding materials, and organic matter to feed the worms and microbes.
The bokashi method requires a container fitted with a tap fixture, organic waste matter, and a substrate (such as wheat bran) inoculated with anaerobic bacteria and yeasts. The inoculated substrate is one of the distinguishing features of the bokashi method.
Labor and Knowledge
The amount of knowledge and effort involved in vermicomposting and bokashi also differ. Bokashi is simpler than vermicomposting and requires minimal knowledge or effort. In contrast, there is a higher level of technical knowledge and effort involved in vermicomposting because the earthworms must be cared for correctly.
Differences in Materials and Inputs
The kinds of items and materials used in bokashi and vermicomposting differ. A wider variety of materials and inputs are necessary for vermicomposting than for the bokashi method.
The bokashi method requires two essential items and materials:
- Inoculated substrate
Bokashi requires an airtight plastic container with a tap fixture. The container must have an airtight seal to maintain anaerobic conditions, while the tap is necessary to extract excess liquids produced during the fermentation process.
The second essential component required for bokashi is the inoculated substrate. Fibrous and carbohydrate-rich materials like wheat bran, rice hulls, oats, or newspapers are usually used for the bokashi substrate. The substrate provides a base and an energy source for the anaerobic yeasts and bacteria that perform the fermentation process.
Inoculated bokashi substrate is widely available in garden and health food stores. It is also easy to make bokashi substrate with homemade Lactobacillus culture and soft, shredded materials with high carbohydrate contents.
Vermicomposting requires a few more items and materials than the bokashi method.
To practice vermicomposting successfully, the following materials and inputs are necessary:
- Epigeic earthworms
- A container or bin fitted with a tap
- Bedding materials
Vermicomposting requires at least 1000 epigeic earthworms (about one pound or 0.45 kg) of worms). It is vital to use epigeic earthworms like Eisenia fetida, which can be purchased from vermicomposting worm suppliers.
Vermicomposting also requires a container or bin to house the worms. It’s possible to use almost any kind of container so long as it is moisture-resistant and non-toxic to the worms. The containers also need a tap fixture for draining liquids from the bins, though a properly managed vermicomposting system produces little to no excess liquid.
Bedding materials are also necessary for vermicomposting. Bedding consists of fibrous, high-carbon organ materials such as shredded cardboard, newspaper, coco coir, and dead leaves. The bedding materials provide a habitat for the worms. Bedding also provides the worms and microbes with a secondary food source.
Rough-textured, hard material called grit is also incorporated with the bedding. Earthworms don’t have teeth, so grit helps the worms grind organic matter in their gizzards before microbes in their intestines decompose the material. Materials often used for grit include gravel, sand, and eggshells.
Differences in Organic Matter Processed
A diverse range of food wastes and other organic materials can be fermented or decomposed in bokashi and vermicomposting systems. However, bokashi can process a broader range of organic materials than vermicomposting, which must cater to the specific preferences and tolerances of the earthworms.
Virtually any type of organic matter can be fermented in bokashi bins, including food wastes that can’t be added to vermicomposting systems, such as:
- Dairy products
- Highly-artificial foods (junk foods)
- Acidic foods (like citrus)
- Pungent foods (like onions and garlic)
The wide range of organic materials that can be processed through bokashi fermentation is one of the most crucial advantages of this method.
Fermentation vs. Decomposition
Bokashi and vermicomposting transform organic waste through starkly different natural processes.
As noted earlier, bokashi involves anaerobic microbes that ferment organic materials instead of decomposing them. Vermicomposting, by comparison, is an aerobic process that decomposes organic matter with earthworms and mesophilic bacteria.
The bokashi method transforms organic materials through an anaerobic fermentation process. Fermentation involves anaerobic bacteria and yeasts that release carbohydrates and sugars bound up in the organic matter by releasing enzymes.
The bokashi fermentation process is considerably quicker than the aerobic decomposition process in vermicomposting.
The anaerobic microbes create rapid biochemical changes in organic matter, making its minerals and nutrients more bio-available to other organisms.
The microbes also release lactic acids and other acidic compounds that lower the pH of the organic matter. These highly acidic conditions preserve the form and content of the organic material because such low pH levels are not tolerated by the kinds of microorganisms that would otherwise decompose that organic matter.
In bokashi, the primary anaerobic microbes that ferment organic matter include Lactobacillus bacteria, purple non-sulfur bacteria, and yeasts like Saccharomyces. A proprietary blend of these microbes called Effective Microorganisms® is commonly used in bokashi to provide the necessary microbial inoculation, though homemade Lactobacillus serum (whey) can be equally effective.
Vermicomposting: Aerobic Decomposition
In contrast to bokashi, Vermicomposting is an aerobic decomposition process performed by earthworms and mesophilic bacteria. In aerobic decomposition (or bio-oxidation), macro and micro-organisms break complex organic compounds into simple, stabilized compounds in the presence of oxygen.
During the aerobic decomposition process, macro-organisms like millipedes, beetles, and worms break large particles of organic matter through physical decomposition. Microorganisms use enzymes to decompose small particles of organic matter biochemically.
Organic matter is made from complex, unstable molecular bonds between carbon, hydrogen, and oxygen. During aerobic decomposition, oxygen molecules are removed, transforming the molecules in the organic matter into simple, stable carbon-hydrogen bonds.
Once the complex compounds in organic matter decompose into simple, stable molecular structures, the organic matter becomes resistant to further decomposition. The minerals and nutrients in decomposed organic matter also become more bio-available because simple organic compounds are easier for plants and animals to access than complex compounds.
In vermicomposting, epigeic or surface-swelling earthworms working in partnership with mesophilic bacteria perform the aerobic decomposition process. Eisenia fetida (red wiggler) is the most common epigeic earthworm species used in vermicomposting. Mesophilic (moderate temperature) bacteria exist on the organic matter and in the worms’ intestines.
The worms physically grind organic matter into tiny particles and pass it into their intestines, where bacteria from their gut micro-biome use enzymes to biochemically decompose the complex organic compounds into more simple, stable molecular forms.
Knowledge and Effort Involved
In general, bokashi requires less knowledge and effort than vermicomposting:
Bokashi: A Simple and Easy Method
Bokashi is a simple method requiring minimal knowledge and effort. Food waste is added to a container and sprinkled with an inoculated substrate.
Once the container has been filled and left to finish fermenting, it is emptied into an outdoor compost pile (or buried in the ground) to undergo decomposition.
Vermicomposting: A Technical and High-Maintenance Method
Vermicomposting requires more knowledge and effort than bokashi because earthworms are involved.
Technical knowledge is required to set up vermicomposting bins and correctly select and arrange the bedding. A reasonable understanding of epigeic earthworms’ life cycle and behavior is also necessary for maintaining healthy, productive worm populations in vermicomposting.
Compared with bokashi, vermicomposting bins also require more effort to maintain. The worm bins must be cleaned and refilled with bedding every few months. To keep the worms healthy, environmental conditions must also be monitored and managed in the worm bins (especially temperature and moisture levels).
In addition, harvesting vermicompost requires more technical knowledge and effort than bokashi. The earthworms must be carefully removed from the vermicompost and returned safely to a newly prepared bin. Technical know-how and painstaking effort are also required to separate the worm castings from the vermicompost.
The Final Products: Nutrient-Rich Soil Amendments
Bokashi and vermicomposting create vastly different but equally valuable end products. The bokashi method ferments organic matter to create a pre-compost product. Vermicomposting decomposes organic matter into a stable organic material called vermicompost.
The bokashi produces a sweet, yeasty-smelling pre-compost material with most of its carbohydrates and sugars removed while retaining its original size, shape, and contents. This fermented bokashi material is highly acidic and must be decomposed by aerobic microbes in a compost pile before use.
The fermented pre-compost material produced through the bokashi method contains:
- Essential plant nutrients and trace minerals
- Plant growth hormones
- Abundant and diverse populations of beneficial bacteria and fungi
Due to the fermentation process, the nutrients and minerals in the bokashi pre-compost material are highly bio-available for plants and animals.
Vermicompost: Decomposed Organic Matter and Worm Castings
The vermicomposting method produces a soil amendment called vermicompost, which is a mix of worm castings and partially decomposed food wastes and bedding materials. Vermicompost is made of fine particles and has a light, fluffy texture. It is possible to apply freshly harvested vermicompost to the soil.
Worm castings are the most valuable ingredient in vermicompost. The tiny chocolate-brown castings can be removed from vermicompost and applied separately as a soil amendment and fertilizer or mixed in water and applied to plant foliage.
The castings contain high amounts of:
- Essential plant nutrients and trace minerals
- High proportions of nitrogen in nitrate form (which is more plant-available)
- Humic and fulvic acids
- Beneficial bacteria
Worm castings contain diverse and abundant populations of beneficial rhizospheric bacteria such as Azospirillum, Pseudomonas, Bacillus, Actinobacteria, and Rhizobium. Rhizospheric bacteria live in the rhizosphere (or root zone) and perform many crucial services to plants.
The rhizospheric bacteria that are contained in worm castings support and enhance plant health and growth by:
- Fixing atmospheric nitrogen in the soil for plants to use
- Making nutrients like phosphorous more soluble and plant-available
- Releasing plant growth hormones like auxins and cytokinins
- Suppressing fungal diseases by producing glucanase and chitinase enzymes
The rhizospheric bacteria, abundant nutrients, and beneficial compounds in worm castings significantly increase plant health, vigor, and beauty.
Bokashi and vermicomposting are different methods for transforming organic matter into distinctive but equally valuable soil amendments.
In the bokashi method, the organic matter is fermented by anaerobic yeasts and bacteria. The fermentation process preserves but does not decompose the structure and contents of the organic matter. Bokashi produces a fermented pre-compost material rich in nutrients, minerals, and beneficial micro-organisms.
A crucial advantage of the bokashi method is that any type of food waste can be fermented. However, the primary disadvantage is that the fermented organic matter has a very low pH and must undergo decomposition by aerobic microbes before being used as a soil amendment.
The vermicomposting method involves an aerobic decomposition process performed by epigeic earthworms and mesophilic bacteria. The worms decompose organic matter physically, while the bacteria use enzymes to decompose organic materials biochemically.
Unlike the bokashi method, vermicomposting cannot process meat and dairy products. Vermicomposting also excludes foods that are oily, pungent, or acidic.
The final product of vermicomposting also differs considerably from fermented bokashi pre-compost. Vermicomposting produces a finely textured mixture of partially decomposed, carbon-rich bedding materials and worm castings. In contrast to bokashi pre-compost, bokashi met vermicompost, and castings can be used immediately as a soil amendment.
The castings are the most crucial part of the vermicompost mixture and contain high levels of essential plant nutrients. Worm castings also contain diverse and abundant populations of beneficial rhizospheric bacteria that support the health and growth of plants.