Understanding the role of soil biology in cannabis cultivation is a vital step towards optimal plant health. Having healthy soils will have an impact on everything from plant growth to yield.
Soil microbes can help unlock locked-up nutrients in the soil and release them into a form that plants can use. This is done by metabolising inorganic compounds into organic forms that are easier for plants to absorb.
Microbial Communities
The cannabis industry is booming, and many cultivators are looking for ways to improve yields and phytocannabinoid and terpene profile. One of the most effective methods is relying on organic living soils. These are teeming with healthy microorganisms that help break down and release nutrients into the root zone of plants.
These microorganisms also help metabolise locked-up nutrients, making them available to plants. These microbial activities are often referred to as ‘nutrient cycling’, and it is thought that this helps plants grow in more efficient ways.
In addition, microbes can help plants absorb minerals that are otherwise difficult for them to extract from the soil. These minerals can include nitrogen and phosphorus, which are typically bound within inorganic molecules.
Several studies have shown that plants with more microbial associations tend to have better nutrient uptake and higher terpene concentrations. This is thought to be because they utilise the benefits of a symbiotic relationship with microorganisms like bacteria and fungi.
Researchers have also found that microbial communities can be highly diverse, and even change from plant to plant. For instance, some plants have a mycorrhizal fungi that binds with the roots of plants and allows them to access more nutrients than they could with their own roots alone.
In other cases, plants may have an ectosymbiotic community of microbes that live with the leaves. This can be beneficial for the plant, as it can access more oxygen, and nutrients that are normally locked up within the leaves of the plant.
However, in some instances, these microbial relationships can have the opposite effect on plant health. For example, some fungi can cause the plants to become brittle and weaker.
This can be a serious concern for both the plant and the grower, as the plants may not grow as efficiently or produce the desired amount of terpenes. This is why it is important to understand the role that microorganisms play in plant health and growth.
This is why Brandon Rust of Dagga Garden and Bokashi Earthworks has developed biological crop steering as a method for improving cannabis cultivation outcomes. Using this strategy, Rust focuses on specific microorganisms to trigger targeted outcomes. He also uses continuous soil testing to track his plants throughout their life cycle.
Nutrient Cycling
Cannabis is a plant that requires numerous nutrients in order to grow and produce healthy buds. Some of these elements are called macronutrients, while others are known as micronutrients.
Nitrogen is one of the most important, since it plays a vital role in chlorophyll formation. A deficiency of this nutrient can lead to brown spots and slow growth in plants.
Phosphorus is also needed at all stages of a plant’s life cycle. If a cannabis plant lacks phosphorus, the leaves turn blue-green and develop brown spots, along with other problems.
Potassium is the last of the ‘big 3’ nutrients, and it plays a key role in photosynthesis and cellular development. A plant with too much potassium will have shrivelled leaves and drooping stems.
The nutrient cycling process is a natural process that links living organisms and non-living objects through the flow of nutrients. This cycle of carbon, nitrogen and phosphorus is essential to a healthy ecosystem.
Soil is the major “switching yard” for these cycles. It stores, moderates the release of, and cycles carbon, nitrogen, phosphorus, as well as many other nutrients.
Nutrient cycling in soil is a complex, step-by-step process that involves virtually all soil organisms. It begins with decomposition, which is the breakdown of organic matter into simpler compounds by fungi, bacteria and earthworms. The residue left behind in soil is then transformed by beneficial microorganisms into highly complex organic compounds called humic substances.
This chemistry takes place over years, centuries and millennia. It concentrates nutrients on the surface of the soil, where they are easily available to the microorganisms and plants that live there.
To maximize the benefits of nutrient cycling, we must preserve the nutrients in our soils. This is best done by avoiding the use of synthetic fertilizers and instead composting or using an organic approach to fertilization.
Fertilizers can contain a lot of chemicals that are harmful to humans and plants. In addition, they can affect the flavor and aroma of marijuana buds, which is why some gardeners choose an organic approach to cannabis cultivation.
Phytoremediation
Phytoremediation is a growing area of study and research in the field of soil biology, specifically in the use of plants to remediate contaminated sites. Often used to remove toxic materials from brownfields, soil, and water, phytoremediation is a viable alternative to traditional methods such as excavation or drilling.
Using certain species of plants that can hyper-accumulate toxins (without harmful effects), phytoremediation is a natural and eco-friendly way to clean heavy metals, pesticides, solvents, explosives, crude oil, and other contaminants from land sites that have been polluted. Several types of phytoremediation techniques exist, including phytoextraction, phytodegradation, and phytostabilization.
The ability of plants to accumulate pollutants is one of the most important considerations in deciding which phytoremediation technique to employ. Plants are able to accumulate metal contaminants by storing them in their root tissue, absorbing them through their leaves and stems, or producing enzymes that help break down the substance into less toxic forms.
Some plants also produce chemical compounds to immobilize contaminants at the interface between roots and soil, preventing them from spreading. This process may be useful for sites with shallow contamination or where the contaminant is not bioavailable.
Plants also degrade chemicals in the soil by releasing toxin-degrading enzymes into the soil, or by extracting and digesting them. Those enzymes can be present in the soil’s rhizosphere, where they interact with the soil bacteria that naturally live there.
This interaction results in the creation of a complex that filters out and slowly degrades organic chemicals, while promoting the growth of the plants that are part of the remediated site. The result is a natural, eco-friendly, and cost-effective method of cleaning up contaminated sites that would otherwise be buried or demolished.
Another advantage of phytoremediation is that it can be implemented in conjunction with other remediation methods. For example, an experiment in Canada used phytoremediation to restore lakes from eutrophication, which occurs when excessive nutrients in the water cause microscopic algae to reproduce too quickly and negatively affect other aquatic life.
Phytoremediation has several benefits for a site, but it requires more time than other approaches and may not be widely utilized due to a lack of trust and understanding in the field. To increase the effectiveness of phytoremediation, more research needs to be done to understand how it works.
Pest Management
When it comes to growing cannabis plants, understanding the role of soil biology is a must. This is because soil biology plays an important role in creating a healthy and vibrant plant. It also serves as a vital protective barrier against pathogens and pests that may damage your crop.
A well-managed soil environment with diverse microbial life enhances plant health and resistance to pests. These microbes are able to change hormonal signalling, repel or outcompete pathogenic microbes, and boost nutrient uptake.
These microbes are essential for boosting your cannabis plant’s immunity against disease and helping it to grow in a way that is more resilient and resistant to pest attacks. They also help to build up a rich and organic compost that is perfect for your crop.
Whether you are cultivating your cannabis in an outdoor or indoor environment, there is no doubt that the cultivation process impacts the environment in a variety of ways. For example, if you choose to grow your plants indoors, you may be responsible for lighting and ventilation that release CO2 into the atmosphere.
Furthermore, you may be responsible for the application of pesticides. These are used to kill or control pests that can harm your cannabis plant or other plants, animals, and/or wildlife in your growing area.
It is important to understand that some of these chemicals can also negatively affect non-target organisms and the environment, including your soil, water, and air quality. Chemicals also have a high biomagnification effect, meaning they are often passed along the food chain and can impact the health of human and animal populations as well.
There are a few different methods you can use to control pests in your cultivation, and they include biological management, mechanical controls, and physical barriers. Biological management involves using natural predators, parasites, and diseases that are found in nature to reduce the number of pest species in a given area.
