1 Introduction

In recent years, sustainable agriculture has emerged as a critical priority deal with issues including climate change, environmental degradation, and food security [1,2,3]. One promising practice that has gained significant attention for its potential in achieving agricultural sustainability is vermicomposting [4]. As an eco-friendly, high-nutrient biological fertiliser, vermicompost is believed to hold the key to significantly enhancing the growth and yield of various field crops, such as vegetables, flowering plants, and fruit trees [2, 5]. Moreover, vermicomposting offers a holistic approach towards environmental restoration, nutrient-rich biofertilizer production, and the cultivation of sustainable crops. Vermicomposting, a process harnessing the natural abilities of earthworms, has been recognized for its exceptional role in transforming organic waste into a valuable resource known as vermicompost [6]. This resulting material bears a higher concentration of essential nutrients compared to conventional compost and manures, rendering it an ideal biofertilizer for fostering crop growth and enhancing soil quality. The utilization of vermicompost ensures the efficient recycling of organic matter, contributing to waste reduction, mitigating the burden on landfills, and promoting a circular economy [7, 8].

At the core of vermicomposting lies the intricate interaction between earthworms and organic waste, which leads to the breakdown of the latter into materials resembling precisely ground peat [9]. The involvement of various microorganisms in the process further enriches vermicompost with essential nutrients and beneficial microbes, establishing it as a potent natural growth stimulant and soil conditioner [10, 11]. The increased nutrient availability, disease suppression, and overall plant health attributed to vermicompost application demonstrate its potential to revolutionize agricultural practices [7]. Beyond the production of nutrient-rich vermicompost, the process also yields a valuable byproduct known as vermi-wash. This nutrient-dense liquid, derived from the leachate of vermicompost, contains enzymes, plant growth hormones, vitamins, and essential micro and macronutrients [3]. The application of vermi-wash has been shown to confer multiple benefits to crops, such as improved resistance against diseases, enhanced seed germination, and overall plant vigor [10]. Vermi-wash and cow urine contain plant nutrients, vitamins, and elements that promote plant growth. A combination spray of 10% cow urine and 10% vermi-wash resulted in increased plant height, branches per plant, and seed yield compared to alternative treatments [11]. Vermi-wash shows promise as a viable biological method for transforming food, medical, and paper waste into organic material rich in nutrients, thereby decreasing dependence on synthetic fertilizers [3, 8, 12]. The integration of vermi-wash into agricultural practices showcases the broader potential of vermicomposting to augment crop performance and ecological sustainability [1]. IrsaShafique et al., have summed up the impact of vermicompost on seed germination and growth process the findings indicated that vermicompost proves to be advantageous in terms of germination and plant growth [10]. HeenaKauser et al., studied about the effects of burning biofuel on environmental pollution and later stated that according to their observations vermicompost is one of the most convenient and safe methods of managing organic waste [13]. They have summed up the time required for traditional vermicomposting technique and compared it with rotary drum compost. Matthew Chekwube Enebe et al., have stated the need of vermicomposting along with the benefits and the technologies used to achieve a continuous vermi-reactor system [14]. SudipGhimire et al., (2023) state that certain set of tests were done to check the efficiency of vermicompost on the cultivation of bitter gourd and the results pointed out towards a better yield [15]. McMaster Vambe et al., have studied the increasing risk of global warming happening because of continuous combustion and hence they have reviewed and stated that vermicompost can serve a good alternative to burning organic waste [16]. AnisaRatnasari et al., have emphasized on the issues of soil fertility and have concluded that adaptation of vermicomposting can be beneficial in increasing soil fertility [3].

Vermicomposting, a practice that involves using earthworms to decompose organic waste and produce nutrient-rich compost, has a long and diverse historical background that spans across different cultures and civilizations. The origins of vermicomposting can be traced back thousands of years, where ancient agricultural societies recognized the benefits of utilizing earthworms in their farming practices [1]. The use of earthworms for agricultural purposes can be found in various ancient civilizations. Historical records from ancient Egypt, Greece, and Rome indicate that these cultures utilized earthworms to improve soil fertility and crop yields [12, 17]. The Egyptians observed that fertile soils had a higher abundance of earthworms and recognized their importance in soil health. In Greece, the philosopher Aristotle documented the role of earthworms in soil improvement. Chinese agriculture has a rich history of utilizing earthworms for soil improvement and waste management [12]. As early as the eleventh century, Chinese farmers recognized the value of earthworms in breaking down organic matter and enriching the soil. The practice of vermicomposting, known as "Haitao" in Chinese, involved using earthworms to transform organic waste into nutrient-rich compost for fertilizing fields. During the European Renaissance, interest in earthworms and their role in soil improvement resurged. During the seventeenth century, Charles Darwin, an English naturalist often regarded as the "father of vermicomposting," conducted extensive research on earthworms. His groundbreaking work, "The Formation of Vegetable Mould through the Action of Worms," published in 1881, highlighted the significant role of earthworms in soil formation and fertility. Darwin's work sparked interest in earthworms and their potential agricultural benefits. In the twentieth century, the understanding of vermicomposting expanded with scientific research and technological advancements. Researchers and scientists began to study the impact of earthworms on soil health and crop productivity more systematically. Practical applications of vermicomposting were explored, and its potential as an environmentally friendly waste management solution gained attention [8, 14].

Over the last few decades, environmental concerns, such as soil degradation, water pollution, and climate change, has prompted a renewed interest in sustainable agricultural practices. Vermicomposting has emerged as a promising solution due to its ability to recycle organic waste, reduce greenhouse gas emissions, and improve soil health [13, 18]. Governments, organizations, and farmers worldwide have increasingly adopted vermicomposting as a viable and eco-friendly method for waste management and agricultural enhancement [19]. Today, vermicomposting continues to be a subject of ongoing research and development. It is recognized as an essential component of sustainable agriculture and an environmentally responsible approach to waste management. The diverse historical background of vermicomposting showcases its enduring relevance and potential to address contemporary challenges related to food security, soil degradation, and environmental sustainability [10]. As research in this field progresses, vermicomposting is expected to play an increasingly vital role in shaping a more resilient and sustainable future for agriculture and the environment.

The main goal of this study work is to clarify the significance of vermicomposting as a sustainable waste management solution and an eco-friendly approach to enhance agricultural productivity. It serves to underscore the importance of comprehending the composition and quality of vermicompost, the selection of appropriate materials for the process, the step-by-step vermicomposting procedure, and the subsequent effects on crop performance. By examining these crucial aspects, the paper aims to provide a comprehensive understanding of potential of vermicomposting for transforming traditional agricultural systems into more environmentally friendly, economically viable, and resilient models for a sustainable future.

2 Significance of vermicompost in advancing sustainable agriculture and environmental resilience

The importance of vermicompost in modern agriculture and environmental sustainability cannot be overstated. Vermicompost serves as a high-quality, nutrient-rich biofertilizer that offers numerous benefits for soil health, crop productivity, and waste management [2, 8, 20]. One of its primary advantages lies in its unique composition, enriched with essential plant nutrients, humic substances, and beneficial microorganisms [9, 13]. These components work synergistically to improve soil structure, enhance nutrient availability, and foster water retention capacity, leading to increased crop yields and improved plant health. Additionally, vermicompost exhibits higher Cation Exchange Capacity (CEC) compared to traditional compost, allowing it to retain and release nutrients more efficiently over time, providing sustained nourishment to plants [5, 21]. By reducing the dependency on synthetic fertilizers, vermicompost mitigates environmental pollution and reduces the carbon footprint associated with conventional farming practices. The adoption of vermicomposting also facilitates the diversion of organic waste from landfills, thus minimizing greenhouse gas emissions and contributing to a more circular and sustainable waste management system [12, 14]. As a natural biofertilizer, vermicompost plays a pivotal role in restoring soil fertility, promoting soil biodiversity, and enhancing the overall resilience of agricultural systems. Its significance in fostering environmentally-friendly and economically-viable agriculture makes it a valuable tool for achieving long-term food security and sustainable development [12]. As research continues to explore the potential applications and improvements of vermicompost, its importance in modern agriculture will continue to grow, offering a promising solution to address the challenges of global food production and environmental sustainability [2].

This study presents a novel viewpoint on the numerous advantages of vermicomposting for environmentally resilient agriculture and sustainable agriculture by cleverly combining historical knowledge with contemporary applications.

3 Raw materials for vermicomposting

Vermicomposting relies on a range of decomposable organic materials to produce nutrient-rich worm castings. The composting materials include various sources of organic waste, such as animal excreta, kitchen trash, farm leftovers, and forest litter. Among the main components, animal excrement, particularly cow dung, is commonly used along with dried and chopped crop leftovers. To enhance the quality of vermicompost, a combination of leguminous and non-leguminous agricultural leftovers is often employed, as it provides a balanced mix of nutrients for the earthworms [2, 22].

Earthworms play a crucial role in the vermicomposting process and come in various species, including red earthworms, nightcrawlers, and others. Among these, the red earthworm stands out due to its rapid multiplication rate and efficiency in converting organic waste into vermicompost in a relatively short period of 45–50 days. These red earthworms are surface feeders, which mean they process organic materials from the top layers of the compost pile [23]. This characteristic makes them highly effective in transforming the organic matter into valuable vermicompost. The combination of carefully selected composting materials and the appropriate species of earthworms creates an ideal environment for vermicomposting. As the earthworms consume the organic waste, they break it down and excrete nutrient-rich worm castings, which are highly beneficial for soil fertility and plant nutrition [24]. The process of vermicomposting thus offers a sustainable and efficient method of converting organic waste into a valuable resource while supporting the growth and reproduction of earthworm populations [6, 25].

Figure 1 illustrates the potential agro-industrial processing wastes that can be utilized as feedstock for the vermicomposting process. Vermicomposting utilizes a variety of raw materials, each contributing distinct properties to the process. Agricultural waste, including crop residues, improves compost aeration and introduces essential organic matter [5, 26]. Food processing wastes, including discards from fruits, vegetables, used cooking oil, and animal processing, enrich the compost with diverse nutrients and enhance microbial activity [2, 26]. Wood processing waste, in the form of sawdust and wood chips, balances the carbon-to-nitrogen ratio and provides structural support [27]. Industrial wastes diversify nutrient sources, demonstrating the adaptability of vermicomposting to various waste streams. Local organic wastes, sourced locally, contribute to microbial diversity and overall organic matter. Fruits and vegetable processing waste introduces readily decomposable organic matter, enriching the compost with essential nutrients and supporting earthworm activity. This diverse mix of raw materials underscores the versatility of vermicomposting in efficiently converting organic waste into nutrient-rich vermicompost, offering valuable benefits for soil health and plant nutrition. Vermicomposting is a sustainable waste management technique that employs earthworms to decompose organic waste materials, converting them into nutrient-rich vermicompost [28, 29].

Fig. 1
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Potential wastes from agro-industrial processing [26]

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4 Procedure and stages for vermicomposting

The vermicomposting process involves several stages and steps to efficiently convert organic waste into nutrient-rich vermicompost using earthworms. Here is a step-by-step procedure for vermicomposting:

4.1 Selection of earthworm

Surface-dwelling earthworms are the preferred choice for vermicompost production, while underground-dwelling earthworms are not suitable for vermicomposting purposes. Among the potential vermicomposting worms, African earthworms, red worms, and composting worms can all be utilized. African earthworms are a popular choice for vermicomposting because of their efficiency in creating greater amounts of nutrient-rich vermicompost in less period of time [12]. They are recognized for their adaptability and prolific reproduction. Red worms are surface-dwelling organisms that are highly skilled in breaking down organic matter from the upper layers of compost, allowing waste to be quickly turned into useful compost. The efficiency of vermicomposting is enhanced by composting worms, which are specialized in processing organic materials. Their capacity to adapt and efficiently consume organic waste results in complete breakdown of waste and nutrient enrichment [2]. In fact, a combination of these three worm species can be employed for efficient vermicompost production. However, the African worm stands out as the top choice among the three due to its ability to produce a larger quantity of vermicompost in a shorter period and generate a higher number of offspring during the composting process [1].

Figure 2 presents an illustration of three types of earthworms—African earthworms, red worms, and composting worms, each contributing significantly to the vermicomposting process.

Fig. 2
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Types of Earthworms (a) African earthworms, (b) Red worms, and (c) Composting worms

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4.2 Site selection

Vermicompost production can be established in any location that provides shade, high humidity, and cool temperatures. Unused structures like abandoned cow or poultry sheds can be repurposed for this purpose. When opting for an outdoor setup, a shaded area is carefully selected to shield the process from direct sunlight and rain. Installing a thatched roof can further protect the vermicomposting area. To cover the organic waste heaped for vermicomposting, wet gunny bags are utilized, ensuring the ideal conditions for earthworms to thrive and facilitate the efficient breakdown of organic materials into nutrient-rich vermicompost.

Figure 3 depicts the site layout for vermicomposting from a top view perspective. The illustration showcases the arrangement of various components and structures involved in the vermicomposting process. This setup is designed to create an ideal environment for the earthworms and ensure efficient vermicomposting, leading to the production of high-quality vermicompost for agricultural use and sustainable waste management.

Fig. 3
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Site layout for Vermicomposting from Top

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4.3 Vermiculture bed preparation

The High-Density Polyethylene (HDPE) Vermicompost Bed is a remarkable innovation designed to facilitate efficient vermicomposting and organic manure production for agricultural use. Its features include exceptional durability and easy installation, ensuring a user-friendly experience. The bed is constructed from long-lasting HDPE material that is UV stabilized and protected, guaranteeing its resilience to withstand environmental conditions. Measuring 4 × 2 × 1 feet and with a rectangular shape, the bed provides ample space for vermicomposting activities. With 16 pockets for bamboo placement, it offers excellent support for thriving habitat of earthworms. To utilize the HDPE Vermicompost Bed effectively, a simple step-by-step process is followed. First, the bed is prepared by adding a layer of soil as the base, followed by chopped dry straw to enhance moisture retention and aeration for the earthworms. Maintaining the moisture level between 40–50% is crucial for creating an optimal environment.

In Fig. 4, the front view provides a clear representation of the vermicomposting bed arrangement and the essential water sprinkling system.

Fig. 4
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Front view of vermicomposting bed arrangement and sprinkling water system

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4.4 Food for worms for vermicomposting process and watering the beds

Next, aged cow dung, serving as a nutritious food source for the earthworms, is added to the bed. If the cow dung is dry, a sprinkling of water can be applied. The layering process continues with the addition of chopped dry straw until the Vermi Bed is fully filled. Uniform distribution of cow dung within the bed is emphasized to ensure balanced nutrient distribution. Sprinkling water on top helps maintain the required moisture for the activities of earthworms. The Vermibed does not necessitate daily watering, but it is essential to maintain a consistent moisture level of around 60% throughout the designated period. If additional moisture is required, it is recommended to spray water over the bed rather than pouring it. This careful moisture management ensures a conducive environment for earthworms and promotes effective vermicomposting processes. Upon completion, introduce the earthworms into the Vermi Bed and cover it to avoid direct exposure to sunlight. The vermicomposting process takes approximately 60–80 days for the compost to mature.

4.5 Selection for vermicompost production

It involves choosing appropriate biodegradable waste materials that are conducive to the vermicomposting process. Various sources of organic waste can be utilized, such as farm wastes, vegetable market trash, crop leftovers, agro-industry waste, flower market waste, and fruit market waste. These materials serve as excellent feedstock for earthworms to convert into nutrient-rich vermicompost. When using cattle dung for vermicomposting, it is essential to dry it in the sun before adding it to the vermibed. Drying the cattle dung helps to reduce excess moisture and create a more balanced environment for the earthworms to thrive. For other organic waste materials, a predigestion step is recommended before introducing them into the vermibed. Predigestion involves mixing the waste with cow dung and allowing it to decompose for about 20 days. This process kick starts the decomposition process, making the waste more easily digestible for the earthworms when placed in the vermibed for composting. The stages of preparation of vermicompost bed are shown in Fig. 5.

Fig. 5
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Vermicomposting bed preparation stages

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4.6 Harvesting of vermicompost

Harvesting vermicompost involves identifying the mature compost, which will have a black and grainy appearance once it has undergone complete decomposition. As the compost reaches maturity, the watering should be gradually reduced. To facilitate the migration of earthworms from the compost to partly decomposed cow dung, it is advisable to place the compost over a pile of such material. After approximately 2 days, the compost can be separated and isolated for use, ensuring that the nutrient-rich vermicompost is ready to be applied as a valuable organic fertilizer. The final harvested vermicompost is shown in Fig. 6.

Fig. 6
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Pure organic vermicompost

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The bioconversion process is accelerated under optimal conditions, including controlled moisture, aeration, and suitable bedding materials, with red earthworms completing the transformation in approximately 45–50 days. This process not only yields valuable vermicompost but also mitigates greenhouse gas emissions, particularly reducing methane release associated with traditional composting. Furthermore, vermicomposting is characterized by minimal odor, making it a more pleasant and environmentally friendly waste management solution, particularly suitable for urban and residential settings.

4.7 Precautions to be taken for vermicomposting

In the context of vermicomposting, several key precautions contribute to the success of the process. To prevent earthworm migration into the soil, it is advisable to pack the floor of the vermicomposting unit [3, 30]. Additionally, the use of cow dung that is 15–20 days old helps avoid excessive heat, ensuring a safe environment for earthworms. The organic waste introduced into the vermicomposting system should be free from plastics, chemicals, insecticides, and metals, as these can be harmful to earthworm well-being. Adequate ventilation in the vermicompost bed is essential to support earthworm thriving, and maintaining moisture levels within the optimum range of 30–40% is crucial for efficient decomposition and a suitable environment for earthworm activity [1, 4]. Regular monitoring and adjustment of moisture levels are recommended. Lastly, maintaining a temperature between 18 and 25 °C fosters optimal vermicomposting processes.

4.8 Storing and packing of vermicompost

To store vermicompost, keep it in a dark, cool area with at least 40% moisture to maintain its quality and nutrient content. Open storage is preferable for better aeration and moisture regulation, benefiting the microbial population. Regular water spraying helps retain moisture and supports the thriving microbial community. If needed, a laminated over sac can reduce moisture evaporation, but maintaining a 40% moisture level remains crucial for preserving quality. With proper management, vermicompost can be stored for up to a year without significant loss in quality. Packing can be done before sale to ensure accessibility and promote soil health as an organic fertilizer.

5 Products of vermiculture

The products of vermiculture provide sustainable and environmentally friendly solutions for improving soil fertility, promoting plant growth, reducing the dependency on synthetic fertilizers, and managing organic waste effectively [31]. The utilization of vermicompost and its byproducts supports the principles of circular economy and fosters a more resilient and sustainable agricultural and horticultural practices.

5.1 Vermicompost

The most notable product of vermiculture is vermicompost, also known as worm castings. Vermicompost is the nutrient-rich organic material produced by earthworms as they consume and digest organic waste [6]. It is a dark, crumbly, and odorless material that is teeming with beneficial microorganisms, plant nutrients, and humic substances. Vermicompost improves soil structure, enhances nutrient availability, promotes beneficial soil microorganisms, and enhances overall soil fertility [28]. Its balanced nutrient content and ability to release nutrients slowly make it an ideal natural fertilizer for sustainable agriculture and gardening. vermicompost, has a wide range of chemical and physical characteristics that are beneficial to improving soil. Its granular texture and dark, earthy tint define it physically. In chemical terms, vermicompost is differentiated by larger concentrations of essential nutrients including potassium, phosphate, and nitrogen, as well as enhanced microbial activity and a greater ability to retain water [4].

Figure 7a represents vermicompost, the primary and most sought-after product of vermiculture. Vermicompost is a nutrient-rich organic fertilizer produced through the breakdown of organic waste by earthworms.

Fig. 7
figure 7

Products of vermiculture (a) Vermicompost (b) Vermi-wash (c) Vermiworms

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5.1.1 Nutrient composition of vermicompost

Earthworms play a vital role in the decomposition and transformation of organic wastes, contributing significantly to the enrichment of soil with plant nutrients [3]. The process of vermicomposting involves earthworms consuming various organic materials, such as kitchen scraps, agricultural residues, and animal manure, and reducing the volume of the waste by 40–60% [1]. Earthworms are highly efficient in this process, as each worm can consume organic waste equivalent to its own body weight in a day. As earthworms consume organic matter, they undergo digestion and excrete nutrient-rich waste called worm castings or vermicompost [6]. Remarkably, each earthworm produces castings equivalent to about 50% of the waste it consumes daily. These worm castings have been studied for their chemical and biological properties, revealing their significant contributions to soil fertility and plant nutrition [28].

The moisture content of worm castings typically ranges between 32 and 66%. This moisture level ensures that the castings maintain a suitable environment for beneficial microorganisms, which further enhance nutrient availability and soil health. The pH of worm castings is around 7.0, indicating a neutral pH level [2]. This is beneficial as it ensures that the vermicompost is less likely to cause extreme fluctuations in soil pH when applied, making it suitable for a wide range of plant species. One of the most notable features of worm castings is their significantly higher nutrient content compared to traditional garden compost. Vermicompost contains nearly twofold higher percentages of both macro and micronutrients. Macro-nutrients such as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) are present in higher concentrations, providing essential elements for plant growth and development. Also, the castings contain an increased amount of micronutrients such as iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and boron (B), which are vital for various physiological processes in plants [34]. The presence of these abundant nutrients in worm castings contributes to the improved fertility and nutrient content of soils when vermicompost is applied as a soil amendment or fertilizer. Moreover, rich microbial diversity and beneficial microorganisms of vermicompost enhance soil health, support nutrient cycling, and promote disease suppression, further supporting sustainable and resilient agricultural systems.

Table 1 provides information on the nutrient composition of vermicompost, which is the end product of the vermicomposting process. The table presents the percentage content of various essential nutrients and other important parameters found in vermicompost.

Table 1 Nutrient composition of vermicompost
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Vermicomposting technology offers an efficient means of converting agro-industrial processing wastes into a nutrient-rich resource. These waste materials represent a significant source of energy, protein, and valuable nutrients, which would otherwise go to waste if disposed of in open dumps or landfills [7]. By utilizing vermicomposting, these nutrients are reclaimed and recycled back into the soil through the application of vermicompost as organic amendments in agriculture [15]. This process ensures the sustainability of the ecosystem, as valuable nutrients are returned to the soil, supporting soil fertility and promoting a circular and eco-friendly approach to waste management [16].

Chemical fertilizers provide targeted nutrients with immediate availability, promoting rapid plant growth, but they lack the comprehensive nutrient spectrum and soil health benefits found in vermicompost. Vermicompost, as a biofertilizer, offers diverse nutrients, including micronutrients and organic matter, fostering sustained plant nourishment and contributing to improved soil structure and microbial activity [4, 17].

5.2 Vermi-wash

Vermi-wash is a liquid collected from water passing through vermicompost. It is a mixture of earthworm excretions, mucus, and micronutrients from the soil. When used as a foliar spray or soil drench, vermi-wash helps plants grow better and become more resistant to diseases. It is a clear, pale yellow fluid with reported growth-promoting effects and acts as a natural biopesticide. Vermi-wash contains enzymes, plant growth hormones, vitamins, and essential nutrients, all of which enhance crop growth and productivity while boosting their ability to fend off diseases [21].

The preparation of vermi-wash relies on the principle that earthworms create burrows in the soil, which are inhabited by beneficial bacteria called drilospheres [1]. Water passing through these burrows washes the nutrients to the roots, benefiting the plants. Vermi-wash is typically ready in about 40–50 days and appears as a clear, brown-colored liquid at the bottom of the container. In the face of extensive use of inorganic fertilizers, herbicides, and pesticides, and the strain on water resources in modern agriculture, seeking effective and eco-friendly alternatives like vermi-wash becomes vital for the sustainability of our farming systems. By harnessing the natural processes of earthworms and soil bacteria, vermi-wash proves to be a powerful and environmentally-friendly solution to support healthier plants and foster sustainable agriculture [20].

The nutrient analysis revealed distinct differences between vermicompost and Vermi-wash. The vermicompost exhibited significantly higher nitrogen content, showing a 57% increase, and potassium content, with a remarkable 79.6% increase compared to Vermi-wash. On the other hand, Vermi-wash displayed a substantial 84% higher phosphorous content compared to vermicompost. Moreover, Vermi-wash was notably richer in calcium (Ca) and magnesium (Mg), boasting an 89.1% and 97.6% increase, respectively, when compared to vermicompost. Additionally, Vermi-wash was found to be remarkably higher in sodium content, showing a significant 97.8% difference compared to vermicompost. Figure 7b showcases vermi-wash, a valuable liquid byproduct of vermiculture. Vermi-wash is the liquid that drains from the vermicompost during the composting process [12].

5.3 Earth worms

Vermiculture also yields a surplus of earthworms, which can be utilized as a valuable resource in various ways. Earthworms are highly beneficial for soil aeration, nutrient cycling, and organic matter decomposition [3]. They can be introduced into gardens, agricultural fields, or compost piles to improve soil health and fertility through their continuous burrowing and feeding activities. Figure 7c illustrates vermiworms, the earthworms themselves, which are an integral part of vermiculture. Vermiworms, such as red worms (Eiseniafetida) and African nightcrawlers (Eudriluseugeniae), are instrumental in breaking down organic waste materials into vermicompost [20].

Figure 7 demonstrates the three essential products obtained through vermiculture—vermicompost, vermi-wash, and vermiworms.

6 Effect of vermicompost on agricultural productivity

Vermicompost has a multifaceted effect on agricultural crop performance, influencing various aspects of plant growth and productivity:

6.1 Crop yield

One of the most significant impacts of vermicompost is on crop yield. The nutrient-rich composition of vermicompost provides essential elements like nitrogen, phosphorus, and potassium, which are vital for plant growth and development [1]. The gradual release of nutrients ensures a sustained supply throughout the growing season, leading to increased crop yields [16].

6.2 Seed germination and plant growth

Vermicompost promotes better seed germination rates and supports early seedling growth. The growth-promoting substances and beneficial microorganisms in vermicompost provide a conducive environment for seeds to germinate and young plants to establish robust root systems [10].

6.3 Nutrient availability

Vermicompost enhances nutrient availability in the soil. The organic matter and beneficial microorganisms present in vermicompost aid in nutrient release and improve nutrient uptake by plants [28]. This ensures that crops have access to the nutrients they need, contributing to healthier and more vigorous plant growth.

6.4 Soil structure

Vermicompost improves soil structure by enhancing soil aggregation and aeration. This leads to better water infiltration and drainage, as well as improved root penetration. The improved soil structure fosters healthier root development and supports overall soil health [7].

6.5 Plant protection

The presence of beneficial microorganisms in vermicompost enhances plant protection. These microorganisms compete with harmful pathogens and provide a natural defense against diseases, reducing the need for chemical pesticides [16].

6.6 Water retention

Vermicompost increases the water-holding capacity of the soil. The organic matter in vermicompost helps the soil retain moisture, ensuring a steady supply of water to plants, even during dry periods [13].

6.7 Nutrient cycling

Vermicompost contributes to nutrient cycling in the soil. The breakdown of organic matter by earthworms and beneficial microorganisms releases nutrients, which are then utilized by plants. This continuous nutrient cycling maintains soil fertility and reduces nutrient loss [3, 28].

6.8 Soil health

Vermicompost enhances overall soil health by supporting beneficial soil microorganisms and improving soil structure. A healthy soil ecosystem translates to improved nutrient availability, disease resistance, and sustained crop productivity [12].

The application of vermicompost positively influences agricultural crop performance in various ways, such as increased crop yield, improved seed germination and plant growth, enhanced nutrient availability, better soil structure, plant protection, and water retention. Its role in promoting sustainable and environmentally-friendly agriculture makes vermicompost a valuable resource for farmers seeking to enhance their crop production while supporting long-term soil health and productivity.

7 Conclusion

The research underscores pivotal role of vermicomposting in sustainable agriculture, biofertilizer production, and environmental restoration. It delves into various aspects, highlighting efficiency of vermicompost in managing organic waste, recycling nutrients, and reducing environmental burdens. The paper emphasizes the versatility of raw materials, ranging from farm waste to kitchen scraps, promoting waste reduction and circular economy principles. Procedural details, including earthworm selection and controlled conditions, are elucidated for successful vermicomposting. The study also explores valuable vermiculture products, such as nutrient-rich vermicompost and vermi-wash, as eco-friendly alternatives to synthetic fertilizers, enhancing soil fertility and agricultural productivity. The nutrient composition of vermicompost is detailed, showcasing its diverse essential nutrients and organic matter. The research concludes by affirming vermicomposting as a promising and holistic approach for sustainable agriculture, biofertilizer production, and environmental restoration, aligning with resilience and sustainability goals. This study differentiates itself by presenting a holistic framework that investigates influence of vermicomposting on waste reduction, biofertilizer production, and crop yields, while exploring diverse feedstocks and the combined benefits of vermicompost and vermi-wash.