Written by Peter Debbink, Extraction Supervisor at The Farm — September 20, 2017
Few plants in history have provoked such a strong reaction in society as the cannabis plant, with some segments of the population condemning its use, while others praising its therapeutic potential and medicinal benefits.
As a plant, cannabis is a fascinating specimen and this blog will explore the various botanical aspects and attempt to explain it in a comprehensive, easy to understand manner, as well as briefly examine the history of mankind’s relationship with this plant.
A Brief History of the Cannabis Plant
Before diving headfirst into the botany of the cannabis plant, it is essential to understand how humans have interacted with the plant throughout history, prior to the modern age.
Some of the earliest uses of cannabis were approximately 10,000 years ago in China, where the fibers of the plant were utilized, and the seeds were consumed as a food source. The earliest evidence of inhalation of cannabis smoke, found thus far, dates to the 3rd millennium BC in Romania, where charred seeds were found in a ritual brazier in a burial chamber; however, the earliest written documentation of cannabis smoke inhalation comes from the writings of the Emperor Shennong in 2727 B.C. Since that time, nearly every ancient culture has cultivated cannabis for various applications.
The ancient Assyrians called the plant “qunubu” (rough translation: “way to produce smoke”) and used it in various religious ceremonies. It is from this word that our name cannabis was likely derived. The Assyrians introduced the plant to many cultures including the Scythians, Thracians, and Dacians, all of whom used the plant for various religious and medicinal applications. From there, use of the plant spread throughout the world, with writings documenting its uses and benefits emerging from every culture from the ancient Muslim world to the ancient Greeks.
The first documented therapeutic use of cannabis in Western medicine occurred in the mid-1800’s when an Irish physician William Brook O’Shaughnessy brought a sample back to Britain from Bengal. In the following decades, cannabis and cannabis-derived medicines began to appear in nearly all “Western” cultures.
It wasn’t until the early 20th century that laws began to appear criminalizing the plant, the most notable being the Marihuana Tax Act of 1937 (United States), which effectively prohibited the cultivation, sale, and research into the plant.
With few exceptions (coffee shops in the Netherlands being the most notable), the plant remained criminalized until the passage of Proposition 215 in California (1996), which allowed for the cultivation, sale, and use of cannabis by patients who were given recommendations by their physician. Since then, over half of the United States, and several other countries have passed laws allowing for the use of the plant for both medicinal and recreational purposes.
As the culture continues to evolve at a rapid pace, so too has the research into this plant, with more discoveries being made on a nearly daily basis. This essay is not intended to be an all-encompassing look at this research, but rather an overview of established botanical facts that have been generally accepted as true by the wider scientific community.
Cannabis – A Botanical Wonderland
Before diving into the nuts and bolts of cannabis specifically, it is important to go over a few basic botany terms that can be applied to all plants:
Monoecious – Plant (or invertebrate) that expresses both male and female reproductive organs on a single individual; hermaphrodite
Dioecious – Plant (or invertebrate) that has male and female reproductive organs on separate individuals within a population
Taxonomy – method of classifying organisms
Angiosperm – Plant that flowers and produces seeds as part of the reproductive cycle
Germination – Development of a plant from seed or spore after a period of dormancy
Phenotype – The set of observable characteristics of an individual resulting from the interaction between an individual’s genotype and its environment
Genotype – The specific genetic makeup of an individual
Cultivar – A plant variety that has been produced in cultivation through selective breeding
Classifying the Cannabis Plant
When discussing any plant, it is important to first begin with the plant’s classification, as this helps form the basis of all research done on that plant. Cannabis of all varieties is an angiosperm that is typically wind pollinated and has been found to grow in nearly all environments. Distinct cultivars have been discovered in every temperate and tropical environment, except for humid tropical rainforests. It can range in height, from 1 meter (3 feet) all the way to nearly 4 meters (16 feet) tall.
Depending on the variety it can grow more bush-like (short and squat with many tightly clustered branches) or tree-like (tall with widely spread branches). It is generally dioecious; however, some individuals can express both male and female organs on the same plant (monoecious). Since the bulk of the important components (cannabinoids) are found within the flower of the female plant, most cultivation of cannabis focuses on improving and enlarging the growth of those flowers, as well as the active removal of any potential male plants to prevent accidental fertilization.
As an indirect result of the prohibition of cannabis by most developed nations throughout the 20th century, there has been a distinct lack of formal taxonomic classification of the plant that continues to this day. Most initial taxonomies of cannabis relied on phenotypic data to distinguish the various cultivars, creating three distinct species of cannabis, including cannabis sativa, cannabis indica, and cannabis ruderalis. Since these classifications relied on physical characteristics, each of these three “species” expressed distinct differences in appearance (see figure 2).
More recently, using genotypic data, the larger scientific community has generally accepted that all cannabis cultivars are of the cannabis sativa species, with indica and ruderalis being unique sub-species that can interbreed and successfully reproduce, hence the distinction between species and sub-species.
The Growth Cycle
Cannabis is generally split into two distinct phases: the vegetative growth phase and the flowering phase.
During a typical outdoor growing season, the plant will remain in a vegetative state for the first 2 – 3 months before switching to the flowering phase for approximately 3 – 4 months. In an indoor garden, the vegetative stage is typically 3 – 4 weeks and the flowering phase lasts for 2 – 3 months.
Given that an indoor garden is not subject to the external stimuli present in an outdoor garden, the grower has significantly more control over when to induce flowering, as well as how long the plant will remain in either state. During the vegetative stage, the plant can grow 1 – 2 inches per day, with some strains reaching heights of almost 4 feet in a few weeks.
During the vegetative phase, male and female plants are anatomically indistinguishable; it is only during the flowering phase that the respective organs begin to develop and express themselves.
Flowering is induced by longer dark periods (nights), with the most rapid flower development occurring approximately 3 – 4 weeks after flowering has begun. Male flowers form small loose clusters along branches, while females develop clusters of flowers primarily at the tip of the branch, with smaller clusters forming at varying increments along the branches. (See Figure 3) Males begin shedding pollen approximately 4 – 6 weeks after flowering has begun, with seed germination occurring in the female flower and continuing for approximately 4 – 8 weeks after fertilization.
As has been previously mentioned, the primary focus of cannabis cultivation currently is on the female plants, as they contain most of the active cannabinoids when compared to male plants. Additionally, when a female plant is fertilized, a large portion of the plant’s energy is diverted into seed production and away from cannabinoid production, thus resulting in a lower quality flower for final consumption.
To avoid any potential fertilization, many growers simply clone a plant known to be female (“mother plant”), which circumvents the possibility of having males, since all clones taken from the mother will also be female. This process is straightforward and involves taking a cutting from the mother plant and exposing that cutting to various external stimuli, which induces root development. Once the roots have developed sufficiently, the cutting is transferred into a growing medium and allowed to begin vegetative growth.
What’s to Come
At the time of this writing, there have been over 700 unique cultivars of cannabis that have been identified, with hundreds more likely in existence just waiting to be studied. As the industry continues to grow and attitudes towards this miracle plant continue to change, we here at The Farm look forward to staying at the cutting edge of this exciting new frontier, engaging with the larger scientific community to better understand this plant and all its potential uses. We’re a community of individuals that care deeply about this plant and only by continuing to push forward as a community will we be able to unlock the mysteries hidden in this amazing species.