Walk into a dispensary and you will be offered “strains”: Blue Dream, OG Kush, Sour Diesel, each with its own promised effects. The trouble is that the name on the jar is a weak guide to what is inside it. Studies that tested the chemistry and genetics of named cannabis have repeatedly found that the same name can cover very different plants, and different names can cover nearly identical ones.
Is “strain” the right word for cannabis?
“Strain” is common commercial shorthand, but an imprecise botanical term. It comes from microbiology, where it describes an isolated genetic variant, such as the descendants of a single bacterial colony[1]. The International Code of Nomenclature for Cultivated Plants (ICNCP), the rulebook for naming cultivated plants, calls it a confused term[2]. Nor is “variety” the answer: in botany, a variety is a taxonomic rank, whereas the category for plants selected by people, under cultivated-plant nomenclature, is the cultivar[2].
What is a cultivar?
A cultivar, short for “cultivated variety,” is a group of plants selected by people for a particular trait or set of traits. Under the ICNCP, a cultivar must be distinct, uniform and stable in those traits, and must keep them when it is propagated in the appropriate way[2]. For cannabis, that usually means cloning from a mother plant, or seed from a carefully stabilized line.
A commercial name alone does not show that a product meets that definition.
Do strain names tell you what’s in the jar?
Mostly not. Three large studies illustrate the problem:
- Genetics. A 2019 study of 122 samples of 30 named strains from dispensaries in Colorado, California and Washington found widespread genetic inconsistency between samples sold under the same name, and no genetic split matching “indica” and “sativa”[3]. Our article on the tangle of cultivar names covers this study.
- Chemistry and genetics. Researchers analyzed 2,662 flower samples sold in Nevada’s medical market under 396 names. The samples fell into just three chemical groups by cannabinoid content, with 93% in a single high-THC cluster, and 12 genetic groups[4]. The authors wrote that the names imply “a false sense of diversity.”
- Large-scale chemical testing. A 2022 analysis of nearly 90,000 lab results from six US states found three main terpene profiles, dominated by caryophyllene and limonene, myrcene and pinene, or terpinolene and myrcene. “Indica,” “sativa” and “hybrid” labels aligned poorly with them, and the authors concluded that commercial labels do not consistently match the chemistry[5].
Names are not entirely meaningless, though. In the same 2022 analysis, some labels turned up more often in particular chemical groups, and some strain names were far more chemically consistent than others[5]. A 2021 study found that “sativa” and “indica” plants were genetically indistinct across the genome, yet the labels were associated with a handful of terpenes controlled by terpene synthase genes[6]; see our brief on labels and terpene synthase genes.Where the indica and sativa labels came from, and what they do and do not predict, is the subject of its own article.
In Washington State’s testing data, specific strain names explained a substantial share of the variation in the THC-to-CBD ratio, even though the indica/sativa/hybrid label explained almost none of the variation in THC[7]. A name may hint at a cannabinoid balance or a terpene tendency. It does not guarantee a genotype, a full chemical profile or an effect.
Genetic testing can show how plants are related and help tell them apart, though it cannot reveal a plant’s full chemistry or its effects. What the plant’s genome has shown so far, from the two-gene switch that sets THC against CBD to the single domestication in East Asia, is in our guide to the cannabis genome. conversation with geneticist Philippe Henry explores how genetics can be used to tell cannabis cultivars apart.
What is a chemovar?
A chemovar, or chemical variety, is defined by what the plant contains rather than what it is called. In 2012, Dutch researchers proposed moving “away from Cannabis cultivars, with often vague and unsubstantiated characteristics,” toward chemovars defined by a measured chemical fingerprint of cannabinoids and terpenes. In their analysis, terpenes and minor cannabinoids were what distinguished varieties, and they suggested the market’s many names could be reduced to perhaps two dozen chemically distinct chemovars[8].
Cultivar and chemovar are not competing names for the same thing. They answer different questions. A cultivar is a group of plants people have selected and can propagate true to type; a chemovar describes the chemical profile a plant produces. The two can overlap: a stable cultivar grown under consistent conditions may correspond to a single chemovar, while several differently named plants may share one.
Chemotypes group plants into broader chemical categories. The simplest classification sorts plants into five chemotypes by their main cannabinoids[9], and each chemotype can contain many chemovars:
| Chemotype | Main cannabinoids | Common description |
|---|---|---|
| I | THC dominant, little CBD | “Drug” type; most dispensary flower |
| II | THC and CBD in similar amounts | Intermediate or “balanced” type |
| III | CBD dominant, little THC | “Fibre” type; most hemp |
| IV | CBG dominant | CBG type |
| V | Almost no cannabinoids | Cannabinoid-free type |
Whether a plant is type I, II or III is controlled largely by a single genetic locus, which determines whether the plant makes THCA, CBDA or both[10, 9]. Within each chemotype, terpenes and minor cannabinoids add further layers of difference. Our guide to cannabis terpenes and our guide to cannabinoids explain those compounds.
Breeders now select for minor cannabinoids too. Our article on chemovars with high minor cannabinoids looks at plants bred for compounds such as THCV, one of the varin cannabinoids.
What does “standardized” cannabis mean?
Standardized cannabis is plant material produced to a specification: every batch should meet set limits for its main active ingredients, much like a pharmaceutical product. What else it guarantees depends on the programme that sets the specification. It exists mainly in medical programmes.
The Netherlands offers the best-documented example. The country’s Office of Medicinal Cannabis, part of the Ministry of Health, is the only body authorized to supply medicinal cannabis there, and it dispenses it through pharmacies on prescription. Its products are defined by cannabinoid content; one balanced variety, for example, contains roughly 6% THC and 8% CBD[11]. The plants are grown under controlled conditions[12]. Every batch is tested against a national quality monograph for its content and for pesticides, heavy metals, microbes and aflatoxins, and comes with a certificate of analysis[11].
Even there, standardization is a matter of degree. The office has reported that THC and CBD content varied between batches by about 20%, and that dedicated growing conditions are needed to keep that in check[11].
The composition limits are what make a product standardized. Contaminant testing and good manufacturing practice (GMP) are related quality controls that make a product safer and more consistent, but they are not the same thing as standardization. Unless the programme specifies them, a standardized product need not have the same terpene profile from batch to batch. No specification can promise the same effect in every person.
Consumer markets have moved partway. In Canada, every legal cannabis label must show total THC and total CBD on the front; a strain name is optional information the producer may add[13].
Why does this matter if you buy or use cannabis?
Because a name is not a chemical specification. The same name can describe plants with very different THC levels or terpene profiles, and even THC numbers can vary between testing labs: in Washington State, median THC results for THC-dominant flower ranged from 17.7% at one lab to 23.2% at another[7].
The most useful information is on the certificate of analysis: the measured cannabinoids and, if tested, the terpenes. Our guides to reading a certificate of analysis, how potency testing works and cannabis testing methods explain what those numbers mean. Strain-based shopping lists, such as our page on strains that tend to contain pinene, describe associations, not guarantees.
Is the industry moving away from strain names?
Slowly. Standards bodies are building the vocabulary first. ASTM International’s cannabis committee, D37, maintains a standard terminology for the cannabis industry, updated in 2026[14], but we found no ASTM standard that governs how cannabis varieties are named. For now, the shift is coming from labels that put measured cannabinoid content first and from medical programmes that define products by their chemistry.
The short version
“Strain” is everyday shorthand rather than a precise botanical term, and “cultivar” applies only to plants that are distinct, uniform and stable. Studies have repeatedly found that cannabis names track genetics and chemistry poorly, though some names are more consistent than others. A chemovar describes what is actually in the plant, and standardized medical cannabis goes a step further by holding its main ingredients within set limits. Until names mean more, the label’s numbers and the lab’s certificate are the better guide.
References
- Dijkshoorn L, et al. Strain, clone and species: comments on three basic concepts of bacteriology. J Med Microbiol. 2000;49:397-401.
- Brickell CD, et al. International Code of Nomenclature for Cultivated Plants (ICNCP), 8th ed. Regnum Vegetabile 151; Scripta Horticulturae 10. International Society for Horticultural Science; 2009.
- Schwabe AL, McGlaughlin ME. Genetic tools weed out misconceptions of strain reliability in Cannabis sativa: implications for a budding industry. J Cannabis Res. 2019;1:3. doi:10.1186/s42238-019-0001-1
- Reimann-Philipp U, Speck M, Orser C, et al. Cannabis chemovar nomenclature misrepresents chemical and genetic diversity; survey of variations in chemical profiles and genetic markers in Nevada medical cannabis samples. Cannabis Cannabinoid Res. 2020. doi:10.1089/can.2018.0063
- Smith CJ, Vergara D, Keegan B, Jikomes N. The phytochemical diversity of commercial Cannabis in the United States. PLoS One. 2022;17(5):e0267498. doi:10.1371/journal.pone.0267498
- Watts S, McElroy M, Migicovsky Z, et al. Cannabis labelling is associated with genetic variation in terpene synthase genes. Nat Plants. 2021;7(10):1330-1334. doi:10.1038/s41477-021-01003-y
- Jikomes N, Zoorob M. The cannabinoid content of legal cannabis in Washington State varies systematically across testing facilities and popular consumer products. Sci Rep. 2018;8:4519. doi:10.1038/s41598-018-22755-2
- Hazekamp A, Fischedick JT. Cannabis – from cultivar to chemovar. Drug Test Anal. 2012;4(7-8):660-667. doi:10.1002/dta.407
- Pacifico D, Miselli F, Carboni A, Moschella A, Mandolino G. Time course of cannabinoid accumulation and chemotype development during the growth of Cannabis sativa L. Euphytica. Published online 2007. doi:10.1007/s10681-007-9543-y
- de Meijer EPM, et al. The inheritance of chemical phenotype in Cannabis sativa L. Genetics. 2003;163:335-346.
- van de Velde M (Office of Medicinal Cannabis, CIBG, Netherlands Ministry of Health, Welfare and Sport). Quality issues and medicinal cannabis in the Netherlands. Presentation, US Pharmacopeia workshop; December 2022.
- Office of Medicinal Cannabis (CIBG, Netherlands Ministry of Health, Welfare and Sport). Quality of medicinal cannabis. Accessed 6 November 2026.
- Health Canada. How to read and understand a cannabis product label. Modified 13 May 2026.
- ASTM International. ASTM D8270-26, Standard terminology relating to cannabis. 2026.
This article is an educational summary of published research. It is not medical advice.
Featured image: three cannabis photos by Keloke Grow, via Pexels (Pexels License); combined, edited, cropped and resized.
Editor’s note: Originally published March 2020 by Lance Griffin; rewritten and expanded November 2026.
