Understanding the role of soil biology in cannabis cultivation is essential for cultivators to achieve a successful harvest. This is because plants rely on living soil to survive and thrive.
It’s a well-established fact that the more diverse and beneficial the soil microorganisms, the more resilient your plants will be to pests and diseases. Soil bacteria also release nutrients that are locked up in inorganic molecules, making them easier for your plant to utilise.
Soil Structure
Understanding the role of soil biology in cannabis cultivation is critical for successful production. It is a complex system that involves a wide array of living organisms that occupy different niches and perform a variety of functions. It is also a dynamic and constantly changing environment.
Soil structure determines the arrangement of soil pores and fissures within a matrix of solid materials (soil particles and organic matter). The quantity, distribution and arrangement of these pores determines water holding capacity, infiltration, permeability, root penetration and respiration.
Good or ideal soil has a large volume of pore space, or porosity. This is usually about 50% of the total dry soil mass.
The pore spaces are where all the action takes place. They are filled with water and nutrients, where plants and microorganisms live, where gases, roots and other elements utilise these spaces to travel through the soil, and where bacteria and fungi are retained and delivered.
As the microorganisms grow in numbers to match their environment, they store a lot of carbon, nutrients and water within their bodies. This acts in a sense like a living buffering system, storing these elements until they can be utilised by plants.
Bacteria are an important component of soil biology, as they are the primary decomposers of organic matter. They can break down a variety of plant exudates (the sugars and metabolites excreted from plants) to release useful nutrients.
They can also fix atmospheric nitrogen to be available for future plants. This is done by a group of bacteria called Rhizobium, which infect the roots of legumes. They in turn use carbon from the host to fix atmospheric nitrogen into a form that is available to plants.
Fungi are another class of soil microorganisms that play a big role in soil health and productivity. They are an important degraders of parts of plants and animals that bacteria have a hard time with, such as cellulose and lignin. They can also stabilize soil aggregates by coating their hyphae with a compound called glomalin, which acts as a protective layer to prevent nutrient and water loss.
Soil Aggregation
Soil biology — the processes that influence soil function and health — is one of the most important factors in the success of cannabis cultivation. The process involves the breakdown and development of organic matter and microbial activities that enhance soil stability, structure, and fertility.
Biologically active soils tend to increase their capacity to form aggregates, which helps them hold more water. This is especially true of coarse-textured soils such as clay, says Aaron Daigh, associate professor of soil physics and hydrology at North Dakota State University (NDSU).
Aggregates are made up of many different particles, including microorganisms, fungi, bacteria, and plant roots. They also have pores — spaces in them that help with air and water movement.
Bacteria and fungi play an essential role in this process. These microorganisms produce a variety of mucilaginous polysaccharides, which act like glue to bind clay, sand, and organic materials together into aggregates.
In addition to physical microbial binding, plant roots contribute to aggregate formation by secreting organic compounds called root exudates that bind soil together near the root zone. Fungal hyphae entanglement and weave around soil particles, helping to stabilize aggregates.
Soil microbial biomass can vary from a few hundred pounds per acre to several thousand pounds, according to research from the US Department of Agriculture. The biomass of each species varies throughout the life cycle of the soil, and changes can be influenced by cropping systems and environmental conditions.
While the role of soil biology is complex and often difficult to quantify, it is vital for plant and microbial health. It increases a soil’s ability to hold water, improves the quality of that water, and allows for nutrient transport to plants. It helps to aerate the soil, which is essential for healthy soil.
A high-quality, well-aerated soil is key to the growth of plants and microbial life. A properly aerated soil will have large pore spaces that are capable of holding water and air for plant and microbial respiration. A poorly aerated soil, on the other hand, will have small pore spaces and not allow for adequate air and water movement into the soil.
Soil Fungi
In a living soil, the presence of billions of microorganisms helps to improve the ability of plants to absorb nutrients from the soil. These microorganisms also help to decompose organic matter in the soil. These microorganisms include bacteria, arthropods and nematodes.
Soil fungi can help to protect cannabis crops against disease-causing pathogens and nematodes by forming mycorrhizae networks. These fungi live close to the roots of plants and are in a symbiotic relationship with them. This relationship allows fungi to access nutrients from the soil without needing to compete with the plant itself.
These fungi can be beneficial in helping to produce good yields for cannabis crops. They also help to suppress soil-borne fungal diseases such as Verticillium and Phytophthora.
The fungi have also been found to help cannabis growers cut back on the amount of synthetic products and fertilisers that are used in cannabis cultivation. These beneficial microorganisms can provide a number of key nutrients that plants require, such as nitrogen and phosphorus.
In addition to these benefits, fungi also assist in breaking down organic matter into simpler forms that can be more readily absorbed by plants. They can also be helpful in releasing carbon-rich materials that the plants secrete into the soil, boosting the overall quality of the soil.
When plants are grown in a nutrient-rich soil, their root systems grow and thrive. However, these roots can be easily damaged by the fungi that live in the soil.
To prevent this, it’s important to use a compost mix that contains both green and brown materials. These include grass clippings, leaves and fruit and vegetable scraps. Compost can be turned regularly to ensure that all parts of the heap are accessible for the microorganisms to break down.
Mycorrhizal fungi can be an excellent addition to any soil and are known to be helpful in the production of high yields for cannabis crops. They form hyphae networks that are about 1/60 the diameter of a normal plant root hair and can aid the growth of the plant by allowing it to obtain additional nutrients from the soil.
Microorganisms
Soil biology is the study of the organisms that live in soil. It encompasses microorganisms (bacteria, fungi and algae), plant roots, vascular plants, insects, arthropods, nematodes and other organisms that make up the entire soil food web [5, 6].
Soils are living ecosystems where bacteria, fungi, protozoa and nematodes play a key role in cycling nutrients from organic to inorganic forms available to plants. They also detoxify chemicals that are toxic to plants or can prevent them from absorbing essential nutrients.
Bacteria and fungi are the primary decomposers of organic matter in the soil. They take up a wide range of organic compounds and decompose them into simpler compounds that they can easily absorb, such as sugars, amino acids and proteins. These simple compounds are then absorbed by plants and released into the soil.
There are many different types of bacteria and fungi that inhabit a healthy soil. They can range from microscopic to very large, and their size depends on how well they are able to fit within the soil structure and what materials they can use as sources of carbon and energy.
Fungi and bacteria play a huge part in the cycle of nutrients in the soil, especially nitrogen and phosphorus. These are both vital for the development of strong, healthy plants. They can also break down inorganic chemicals and bind up the organic molecules of minerals to free them up for use by plants.
The importance of the soil’s microbiome cannot be underestimated and should be considered in cannabis cultivation, whether it is indoor or outdoor. This is because these allies of our plants can help to protect them from a range of biotic stresses including excess water, disease and insect pressure.
A major part of their work involves helping to detoxify potentially harmful chemicals such as herbicides that could otherwise linger in the soil and inhibit plants from growing successfully. This is a big advantage for growers who want to reduce the need for chemical fertilizers and pesticides in their gardens.
As well as reducing microbial contamination on your crops, understanding the importance of soil biology can lead to better harvest results and greater profits for you. Using techniques to boost the numbers of beneficial microbes can ensure that your crops are not only growing healthy, but that they will also produce a high quality crop when the time comes for harvesting and packing.
