What really goes into the making of a cannabis flower? Water and light are a must. Fresh air exchange helps to keep detrimental organisms at bay. A fine balance of macro and micronutrients optimize plant physiology, growth, and yields. However, the cannabis microbiome remains an unseen force that lays the foundation to all of this.
Cultivators of the herb go to great lengths to enhance the quality of their buds. Not only does this effort increase the recreational caliber of flowers, but the upregulation of cannabis constituents increases the efficacy of the plant for medicinal purposes.
The Microbiome: The Key To Human And Plant Health
The words “bacteria” and “fungi” often get a bad wrap. These terms are often perceived as dirty, infectious, and disease-ridden. Humans have waged war on these organisms for hundreds of years, and we all engage in rituals of hygiene throughout the day to ensure we minimize our exposure to them.
Far from enemies of our physiology, many microorganisms contribute to what it takes to form a healthy human. They act symbiotically with our cells to enable us to digest food, bolster our immune defences, and quench inflammation.
The discovery and subsequent mainstream exposure of the microbiome have started to change how our culture views these crucial organisms. Critical research surrounding the communities of microbes that reside in the human body started in the late 17th century in Europe. Our understanding of this complex system has evolved radically, and what we’ve discovered has changed the picture of human physiology.
The human organism is 99% microbial in terms of genes. Our bodies host trillions of bacteria, fungi, viruses and other organisms that mostly outnumber our own cells. The process of birth inoculates our gut with beneficial microbes, and they go on to contribute to neurological development, prevent chronic disease, and enable us to get the most out of our food.
In an age where we appear increasingly disconnected from the environment, such data serves as a realisation that we don’t just depend on external species to thrive, we need them to merely survive.
Humans have a tendency to view the world through a homo sapiens-centric lens. The microbiome intimately ties us to the outside world, including the species that we consume. Not only does nurturing our own microbiome enhance our wellbeing, but improving the symbiotic colonies within other organisms — including cannabis — pays dividends when it comes to their effectiveness.
The Cannabis Microbiome
To the naked eye, the cannabis plant appears as a standalone organism distinct from its immediate environment. Through the lens of a microscope, this illusion of the five senses shatters. Cannabis plants host a rich diversity of organisms that forge their microbiome, found both externally on their leaves and flowers, as well as deep inside their vegetative tissues.
The human and cannabis microbiome hold several commonalities. Just as we receive a bacterial inoculation at birth, the cannabis plant begins its relationship with beneficial microbes as a seed. Throughout life, these organisms regulate gene expression, underpin important metabolic processes, and subdue pathogens.
The rhizosphere makes up the region of soil beneath our feet in which plant roots grow. Packed full of both benevolent and hostile species, cannabis seeds must endure the throes of this environment as they germinate.
Fortunately, the seeds harbour a variety of microbes before they open, which go on to inoculate and protect them during the early stages of life. As you watch a seedling break through the soil, you’re laying eyes on a living microhabitat abundant with microbial synergy.
As cannabis plants mature, their populations of microbes are found at every channel through which they interact with the outside world. Above ground, these organisms occupy the plant-air interface, or phyllosphere. Here, species of bacteria, fungi, viruses, yeast, and algae work to promote plant growth, balance carbon cycling, and maintain stress tolerance.
Underground, several species of bacteria and fungi help to manage the root-soil interface. Cannabis plants effectively farm these microorganisms. By exuding carbohydrates into the soil, they attracted synergistic species of mycorrhizal fungi that fuse to their roots.
In exchange for energy-rich sugars, these lifeforms act as an extension of the root system. They break down organic matter by excreting enzymes and shuttle key nutrients into the root system — fueling luscious growth.
Cannabis plants also harbour microbes internally within the endosphere. Known as endophytes, these organisms stimulate plant growth through the manufacturing of hormones, facilitate mineral uptake, provide thermal protection, and neutralize invading pathogens.
Beneficial species of bacteria and fungi occupy every major organ and tissue of cannabis. They are found in the roots, stems, petioles, leaves, and seeds. By nurturing these populations through organic and sustainable practices, growers are able to boost the phytochemicals within this healing plant.
The Soil Food Web: How Microbial Populations Make Better Cannabis
Environmentally-conscious cannabis cultivators are changing the way the world grows weed. They’re stepping away from the reductionist models of “nutrients in, yield out”. Instead, they are turning to nurturing the soil food web to enhance plant health and quality, as well as the biodiversity within their gardens and further afield.
Regenerative agriculture seeks to cultivate plants in a way that builds healthy soil. Currently, conventional agriculture strips away 1-3cm of vital topsoil each year. Not only do regenerative practices help to build soil, but they also produce better-quality plants.
Instead of bombarding the growing medium with artificial fertilizers each growing season, regenerative growers aim to feed the soil instead of the plants. Coined by soil microbiologist Elaine Ingham, the term “soil food web” describes the intricate system of organisms that creates healthy soil through the cycle of life and death.
By adding organic amendments and compost to the soil, growers feed the beneficial communities of fungi, bacteria, and other lifeforms. In turn, they break down this organic matter into nutrients that cannabis plants can use.
The over-application of xenobiotics such as pesticides interrupts the ability of plants to interact with their microbiota. Interestingly, these chemicals create similar disturbances within the human microbiome. By avoiding these substances, regenerative growers allow microbial populations — and cannabis’ ability to synergise with them — to proliferate.
The preservation and cultivation of the cannabis microbiome not only leads to healthier and more productive plants, but it may also improve the quality of the flowers by modulating the production of secondary metabolites such as THC, CBD, and other cannabinoids.
Through the upregulation of phytohormones that stimulate growth and development, endophytes appear to increase the biosynthesis of cannabinoids and terpenes, the major molecules responsible for the therapeutic properties of the herb.
Cannabis & The Human Microbiome: Healthy Soil Makes A Healthy Gut
Research into the effects of cannabis phytochemicals on the human microbiome completes the cycle. By nurturing the soil, we nurture cannabis. By nurturing cannabis, we create more effective medicine that helps to regulate the microbial communities essential to our health and wellbeing.
Cannabinoids interface with the endocannabinoid system (ECS), a body-wide network responsible for maintaining biological equilibrium. ECS receptors exist in the human gut, where they form the microbiota-endocannabinoid system axis. Cannabinoids bind to these receptor sites and influence gut-barrier function, inflammation, and metabolism.
Early research also suggests that THC may help to prevent shifts in the microbial makeup of the gut towards a state of dysbiosis and disease.
Luke Sumpter is a freelance journalist that specializes in health, wellness, and alternative therapies. Currently, he’s working on a dissertation exploring the emerging role of the endocannabinoid system in orthopaedic medicine.