How can you predict the quality and effect of a strain of cannabis? For a start, asking “indica or sativa?” is categorically the wrong question. In truth, these categories mean less and less in a market where virtually all strains have been hybridized for decades.

Medical marijuana users, and anyone who has stepped into a dispensary recently, might be familiar with cannabis strains classified as whether they are sativa or indica dominant. You’ve probably heard indica referred to as ‘in da couch’, implying a sedative, full-body stoned feeling of couch-lock, and sativa being acclaimed for its cerebral uplifting high effect.

The problem with this popular theory? Centuries of cross-breeding and the creative naming of strains means that most cannabis is now a hybrid and, even if you could find a pure sativa or indica strain, it’s the chemical composition of the plant, not the name of it, that will most dictate your experience.

What’s the difference between indica and sativa?

A fulsome explanation starts with a quick botany/Latin lesson. The Cannabis plant is in the Rosales order (along with roses, strawberries, and almonds), the Cannabaceae family (along with hops), Cannabis genus, and its species is sativa (coming from the Latin botanical adjective meaning ‘cultivated’). There are three subspecies of Cannabis: sativa, indica and ruderalis. These classifications are based on visual assessments of the plant, looking at growth height, shape and leaf morphology.

Swedish scientist Carl Linnaeus believed that the cannabis genus was monotypic, a single species, when he named it Cannabis sativa L (for Linnaeus) in 1753. Three decades later, French naturalist Jean-Baptiste Lamarck identified a second subspecies of cannabis, which he named Cannabis indica Lam. because his plant specimens had been collected in India (‘indica’ meaning ‘of India’).

Cannabis ruderalis, a hardy fibrous plant containing little to no psychoactive THC, was discovered by a group of Russian botanists in the early 20th Century and is named after the Latin root word ‘ruderal’, which means weed. Ruderalis can be bred into hybrids as they contain genetics that helps plants grow quickly and ward off pests. Hemp is a cultivated version of cannabis that can be grown from any of the male plants of the subspecies but must contain less than 0.3% THC, according to Health Canada.

At this point it’s impossible to know the exact chemical composition of the historical indica and sativa plants.

Centuries of natural cultivation and hybridization have made it hard to find pure sativa or indica plants because even stabilized ‘pure’ strains can exhibit new traits when grown in different conditions. At this point it’s impossible to know the exact chemical composition of the historical indica and sativa plants.

Visually, there are obvious differences between sativa and indica plants that are a result of their original environments. Sativa traditionally grew in forested valleys in very humid, equatorial locations, so it grows thin and tall — six to 20 feet —with narrow leaves that help with greater respiration, which increases the rate of photosynthesis and flower/seed production.



Indica plants grow short and squat (two to four feet) and have wider, stubbier leaves to minimize water loss through respiration, as they tended to grow at higher mountainous elevations where water was scarce and the air was drier. Indicas also produce more resin to protect themselves against this harsh environment. The short stature and faster flowering time of indica — 6-8 weeks as opposed to sativa’s 9-12 weeks — made it a more popular choice for clandestine indoor growing.

Why does it matter?

Cross-breeding and indoor growing have affected the genetic make-up so much that now nearly all plants are hybrid, however they are not always labelled as such. Customers tend to choose strains based on whether they are described as sativa or indica ‘dominant’. But what you see is not what you get. Centuries of cultivation has made it hard to even find a pure sativa or indica and, unlike other crops such as apples or grapes, strain names are assigned to these plants even as they are grown from seed.

Recently, researchers at Dalhousie University in Nova Scotia found that 35% of cannabis samples were actually more genetically similar to strains with different names than to samples with identical names. They reported their findings in PLOS ONE, a peer-reviewed cannabis publication, to state that the genetic identity of a cannabis strain cannot be reliably inferred by its name or by its reported ancestry.



The report concluded that: “C. sativa and C. indica may represent distinguishable pools of genetic diversity but that breeding has resulted in considerable admixture between the two. While there appears to be a genetic basis for the reported ancestry of many marijuana strains, in some cases the assignment of ancestry strongly disagrees with our genotype data.” For example, the report found that Bob Marley’s alleged favourite strain, Jamaican Lamb’s Bread (100% reported C. sativa), was nearly identical to a reported 100% C. indica strain from Afghanistan.

How does indica vs sativa classification affect your experience?

In short, it doesn’t. Unless you’re a botanist looking at the physical characteristics of the plants, the presence of sativa or indica is irrelevant. Climate, soil type, fertilization methods and harvest times all affect the chemical composition of the plant, even within the same strain. Cannabinoids contents, including CBD and THC, working in an ‘entourage effect’ with terpenes (fragrant oils), are what will ultimately give you an idea of what to expect.

"...the sativa/indica distinction as commonly applied in the lay literature is total nonsense and an exercise in futility."

Renowned Cannabis researcher Dr Ethan Russo concluded that: “There are biochemically distinct strains of Cannabis, but the sativa/indica distinction as commonly applied in the lay literature is total nonsense and an exercise in futility. One cannot in any way currently guess the biochemical content of a given Cannabis plant based on its height, branching, or leaf morphology. The degree of inbreeding/hybridization is such that only a biochemical assay tells a potential consumer or scientist what is really in the plant. It is essential that future commerce allows complete and accurate cannabinoid and terpenoid profiles to be available.”

With Canadian legalization on the horizon, there’s a new push for lab testing and accurate labelling that gives a complete profile of the plant, beyond the simplistic sativa vs indica designation. Read more about how terpenes are a powerful way to distinguish between strains.

