The difference between vermicast, vermicompost, and vermiculite and why you should use all of them in herbal gardening
Our Top Vermicast Products for Your Garden
We can vouch for the validity of vermicast from these products below. Some will give you their microorganism breakdown and NPK breakdown for serious growers! All in all we believe these will help your herbal garden reach peak production!
Best OMRI-Certified Vermicast: Urban Worm Company Vermicast
Runner-Up: Best OMRI-Certified Vermicast : Brut Organic Worm Castings
Cheapest Organic Vermicast on Amazon: Eden’s Best Worm Castings
Best Small Business Vermicast: Brother’s Worm Farm- Worm Castings
Best Vermiculite: Plantonix Pure Bliss Vermiculite
Disclaimer: "Just a heads up, some links in this post are affiliate links. If you click on them and buy something, we might earn a small commission at no extra cost to you. Thanks for supporting our blog! Happy growing!
Organic gardening and sustainable agriculture practices have gained popularity in recent years, leading to the increased use of natural soil amendments and growing mediums. This is true among what we are finding in herbalist communities as many herbalists carry a “like-mindedness” in this vein of sustainable gardening. Erin and I are very passionate about our soil health, and as such are committed to putting posts here from time to time that will focus on the “UNDER” of Herb & Under specifically. We are so passionate about it we made a course “how to start your family worm farm” if you are interested. We are avid worm farmers and use vermicast in almost all our plants. We hope you will find useful information as you consider incorporating vermicast (also referred to as worm castings) to your herbal garden of choice. Additionally vermicompost and vermiculite are other options to consider adding each with distinct properties and benefits. In this comprehensive guide, we will explore the differences between these materials and discuss how and why you should use each.
Vermicast: The (Almost) Pure Form of Worm Poop
What Is Vermicast?
Vermicast, sometimes referred to as worm castings or worm manure, is the end product of the vermicomposting process. We choose to call it by it’s more scientific and accurate name “vermicast.” It is the (almost) pure form of worm poop, with a fine, dark black texture and rich in nutrients, bacteria, and enzymes that benefit plants. Vermicast is often called "black gold" because of its numerous benefits to organic and restorative growers. Few natural fertilizers contain all the beneficial microorganisms that vermicast can offer in a sustainable and eco-friendly way. When we use vermicast we regularly will use them as supplements to the soil for our seedlings, are in ground gardening, and potted plants even as top dressing application.
Benefits of Vermicast
Vermicast offers several advantages to plants and gardens. Equally so to your herbs you might be growing :). Here are a couple.
Nutrient-rich organic matter: Vermicast is rich in essential nutrients such as nitrogen, phosphorus, and potassium, as well as micronutrients that help promote plant growth and improve soil structure.
Water retention: Vermicast can help improve the water-holding capacity of the soil, allowing plants to access water longer and reducing the need for frequent watering.
Beneficial microorganisms: Vermicast is teeming with beneficial bacteria, fungi, and other microorganisms that help break down organic matter, making nutrients more accessible to plants and improving soil fertility.
Pest and disease resistance: The beneficial microorganisms in vermicast can help plants develop resistance to pests and diseases, reducing the need for chemical pesticides and fungicides.
Specific Herbs that benefit from vermicast application:
Here are some herbs that usually benefit greatly from using worm castings as a supplement;
Basil: Worm castings are beneficial for basil as they aid in the growth of vibrant leaves that are crucial, for enhancing flavor and promoting healthy development.
Mint: thrives due to its growth potential when provided with nutrients and helpful microorganisms found in worm castings."
Chives: Worm castings are beneficial, for chives as they can enhance growth and yield more of their slender leaves.
Oregano: This herb thrives in soil that's well drained and fertile with the assistance of worm castings that promote healthier plant growth and higher essential oil output.
Rosemary: benefits, from the soil drainage and aeration provided by worm castings for its overall health and growth requirements.
Thyme: benefits greatly from the slow release fertilizing nature of vermicast and enhanced soil quality that worm castings offer leading to growth and a bountiful yield of aromatic leaves.
Sage: thrives with the rounded nutrients and enhanced soil quality provided by worm castings. There are studies that claim there is more prolific sage production when amending the soil with vermicast." Plus the sage we grow adds a lovely touch of green to my outdoor space.
Lemon balm: thrives in soil, with good drainage that is nourished by worm castings resulting in robust growth and a higher production of leaves.
Cilantro: Just trust us on this one, it explodes with vermicast usage (in a good way).
Keep in mind… Although these herbs typically thrive with vermicast as a fertilizer options; the requirements can differ based on your growing environment and other variables such, as sunlight and soil quality or pH levels*. It's advisable to observe your plants and modify your care regimen accordingly.
How to Use Vermicast
Vermicast can be used as a soil amendment, mixed into potting soil, or applied as a top dressing around plants. It is important to note that vermicast should not be used alone as a growing medium but rather combined with other materials such as soil, compost, or peat moss. To avoid nutrient toxicity, vermicast should make up no more than 30-40%% of the total potting mixture.
Vermicompost: A Mixture of Vermicast and Worm Bedding Residue
What is Vermicompost?
Vermicompost is the end product of the vermicomposting process, a mixture of vermicast and residual material from the worm bedding. You would not think there is much difference, but you would be surprised. It contains slightly fewer living organisms than vermicast but offers additional soil amendment properties due to the presence of worm bedding material. Depending on the bedding material as well, you can find a plethora of organic materials such as wood chips, decaying leaves, overs, and other matter.
Benefits of Vermicompost
Vermicompost offers similar benefits to vermicast, such as:
Improved soil structure: The addition of vermicompost can help improve the structure and texture of the soil, making it more porous and improving aeration and water drainage.
Enhanced nutrient availability: Vermicompost contains a diverse array of nutrients and beneficial microorganisms that help make nutrients more accessible to plants.
Disease and pest suppression: The beneficial organisms in vermicompost can help suppress diseases and pests, reducing the need for chemical interventions.
How to Use Vermicompost
Vermicompost can be used in a similar manner to vermicast, either mixed into the soil, applied as a top dressing, or incorporated into potting mixes. When used in potting mixes, vermicompost should make up no more than 40% of the total mixture to ensure a balanced nutrient profile.
Vermiculite: A Natural Mineral for Soil Amendment and Growing Medium
What is Vermiculite?
Vermiculite is a natural mineral derived from a group of hydrated laminar minerals, formed by the weathering or hydrothermal alteration of certain minerals like biotite or phlogopite. We think these are fancy ways of saying these are rocks in unique forms. It is often used as a soil amendment or growing medium in gardening and horticulture, providing improved water flow and preventing root damage from excessive moisture.
Benefits of Vermiculite
Vermiculite offers several advantages for gardening and agriculture, including:
Water retention and drainage: Vermiculite can absorb several times its weight in water, improving the soil's water-holding capacity while allowing excess water to drain away, preventing root rot and waterlogging.
Aeration: The lightweight structure of vermiculite helps improve soil aeration, promoting healthy root growth and overall plant health.
Nutrient availability: Although vermiculite itself does not contain nutrients, it can help facilitate the absorption of nutrients from other sources, such as fertilizers or compost.
How to Use Vermiculite
Vermiculite can be mixed into the soil, used as a standalone growing medium for seedlings or cuttings, or incorporated into potting mixes. When used in combination with soil, vermiculite should make up 10-20% of the potting material to ensure adequate aeration and drainage.
Comparing Vermicast, Vermicompost, and Vermiculite: Key Differences and Similarities
While vermicast, vermicompost, and vermiculite all offer benefits to plants and soil, they have distinct properties and uses:
Nutrient content: Vermicast and vermicompost are rich in nutrients and beneficial microorganisms, while vermiculite does not contain nutrients but can help improve nutrient availability.
Water retention and drainage: All three materials can help improve water retention and drainage in the soil, with vermiculite providing the most significant improvement in drainage.
Odor and pathogens: Vermicast and vermicompost may have an earthy smell and contain some pathogens and bacteria, while vermiculite is odorless and free of pathogens and bacteria.
Soil amendment vs. growing medium: Vermicast and vermicompost are primarily used as soil amendments, while vermiculite can be used both as a soil amendment and a standalone growing medium for seedlings and cuttings.
Combining Vermicast, Vermicompost, and Vermiculite for Optimal Plant Growth
Vermicast, vermicompost, and vermiculite can be used together in various combinations, depending on the plant or the situation, to create an optimal growing environment for plants:
Vermicast and vermiculite: Mixing vermicast with vermiculite can provide the benefits of nutrient-rich vermicast and improve water retention and drainage of vermiculite. This combination is ideal for container gardening or raised beds.
Vermicompost and vermiculite: Similar to the vermicast and vermiculite combination, mixing vermicompost with vermiculite can provide a balanced growing medium with improved soil structure and water management. Just be on the lookout as you will probably get more water seeping through the containers due to the aggregates comprising the soil.
Vermicast, vermicompost, and vermiculite: For a more comprehensive approach, all three materials can be combined with other substrates such as soil, coco peat, or compost to create a nutrient-rich, well-aerated, and well-draining growing medium. If choosing to use all three, be more generous with using vermicast in a greater portion for the best long-term results of your plants.
BONUS video: Here is a great video on the differences of vermiculite and perlite from Garden Answers on Youtube.
Choosing the Right Material for Your Garden or Farm
The choice between vermicast, vermicompost, and vermiculite depends on your specific gardening or farming needs, as well as the types of plants you are growing:
Nutrient requirements: If your primary goal is to improve soil fertility and provide plants with essential nutrients, vermicast or vermicompost may be the best choice.
Water management: If you struggle with waterlogged soil or need to improve water retention in sandy or fast-draining soil, vermiculite may be the best option.
Soil structure and aeration: If you need to improve soil structure, promote healthy root growth, and optimize oxygen availability for plant roots, a combination of vermicast or vermicompost with vermiculite may be ideal
Sourcing Vermicast, Vermicompost, and Vermiculite?
High-quality vermicast, vermicompost, and vermiculite can be purchased from reputable garden centers, online retailers, or directly from manufacturers. As usual, we promote finding OMRI-certified materials for your organic gardening or trusted sources that you know operate within organic guidelines. Producing high quality vermicast is something we take pride in and specialize here at our small worm farm operation. You can trust when you purchase from us you are getting the most organic and high-quality vermicast around!
Safety and Environmental Considerations
When using vermicast, vermicompost, and vermiculite in your garden or farm, it is essential to consider safety and environmental factors:
Purity and quality: Ensure that the materials you use are free of harmful chemicals, pesticides, or heavy metals that could harm plants, soil, or the environment.
Pathogens and bacteria: Be aware that vermicast and vermicompost may contain some pathogens and bacteria, so it is essential to handle and store these materials properly to prevent contamination or health risks.
Sustainable sourcing: Choose vermiculite products that are sourced from environmentally responsible mining practices to minimize the environmental impact of mineral extraction.
Frequently Asked Questions About Vermicast, Vermicompost, and Vermiculite
Can I use vermicast or vermicompost as a standalone growing medium?
Vermicast and vermicompost are best used as soil amendments or mixed with other substrates, as using them as standalone growing mediums can result in nutrient toxicity and poor plant growth.
How often should I apply vermicast or vermicompost to my garden?
The frequency of application will depend on the specific needs of your plants and soil, but generally, vermicast and vermicompost can be applied one to three times per growing season as a top dressing or mixed into the soil.
Can I use vermiculite for all types of plants?
Vermiculite is suitable for most plant types, but it may not be ideal for some desert plants or plants that prefer well-draining, sandy soils.