Cannabis cultivation
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Cannabis cultivation is the growing of Cannabis sativa for fibre, seed, drug or multi-purpose use. Cannabis is a dioecious annual in the family Cannabaceae with a long history of agricultural use across Eurasia and, through later dispersal, every inhabited continent.[1] Cultivation practices vary by use type, latitude, climate and legal context, ranging from rainfed smallholder fields integrated into mixed cropping systems to fully enclosed indoor production.
The crop is grown for several distinct end products, including bast fibre from the stem, seed for food and oil, drug preparations made from female inflorescences (such as ganja, charas, hashish and sinsemilla), and combinations of these.[2] Modern commercial drug cultivation is largely based on F1 hybrid genetics propagated as clones, often grown indoors or in greenhouses, while landrace populations persist in traditional growing regions through ongoing mass selection by farmers.[3][4] Outdoor production remains the dominant mode worldwide for fibre, seed and traditional drug cultivation, while indoor systems using artificial lighting became widespread in prohibition-era North America and Europe from the 1980s.[5]
History
Cannabis is among the earliest cultivated plants, with archaeobotanical evidence for human use of the genus extending back several thousand years across Eurasia.[6] Cultivation for fibre and seed is documented in Bronze Age south-west China,[6] in Central Asian burials, and in classical sources from ancient India and the Mediterranean.[1] Drug-type cultivation expanded along trade routes during the medieval period, and North African, South Asian and Southeast Asian traditions developed distinct selection pressures and end products. Introduction of cannabis to the Americas occurred through colonial trade and forced labour.[1]
Plant biology
Cannabis is a wind-pollinated dioecious annual, with separate male and female plants in most populations and a hermaphroditic minority.[1] Most varieties are short-day, flowering in response to shortening daylength, although autoflowering day-neutral types occur in ruderal populations adapted to short summers at high latitudes.[7] The plant exhibits substantial phenotypic plasticity in height, branching, leaf morphology and flowering time, and harbours wide genetic diversity across its range.[8][9]
Genomic data support a monotypic genus comprising Cannabis sativa, with infraspecific structure that reflects geography more than use type.[10][9] Vernacular use of "sativa" and "indica" as variety labels does not align with this structure and is treated separately under NLD/BLD classification.
Use types
Cultivation choices are organised around the intended end product:
- Fibre-type (hemp)
- Tall, long-stemmed plants grown at high density for bast fibre in the stem. Sown in spring and harvested at or shortly before flowering. Selection favours stem length and quality over inflorescence development.[1]
- Seed-type
- Plants grown for grain. Selection emphasises seed yield, oil content and ease of harvest. Often dual-purpose with fibre.[1]
- Drug-type
- Plants grown for resin-rich female inflorescences. Includes ganja (dried inflorescence), charas and hashish (separated trichome resin) and sinsemilla (unfertilised inflorescence). The 0.3% THC threshold used in many legal frameworks does not correspond to a botanical category.[2]
- Multi-purpose
- Traditional regional landraces frequently combine two or more uses (fibre and seed, or seed and drug), with the same population yielding different products through farmer selection and post-harvest practice.[1]
Cultivation environments
Outdoor cultivation
Outdoor cultivation is the dominant mode worldwide for fibre and seed crops and for drug-type cannabis grown for traditional or low-cost markets.[1] Outdoor crops follow the natural photoperiod, with planting and harvest timed to the local growing season. Production occurs across a wide range of climates, from temperate continental fibre zones to tropical drug-cultivation areas, with yield and morphology shaped strongly by latitude, altitude and rainfall.[9]
Indoor cultivation
Indoor cultivation became widespread in prohibition-era North America and Europe from the 1980s and remains a significant mode for legal and illegal drug-type production. Indoor systems use artificial lighting to control photoperiod independently of season, allowing multiple harvests per year and tight control over microclimate. Energy inputs per unit yield are substantially higher than for outdoor production.[5]
Greenhouse cultivation
Greenhouse production combines natural sunlight with environmental control. It is used in commercial cannabis industries from the Netherlands to Colombia and is intermediate between outdoor and fully indoor production in input intensity.
Cropping cycle
Propagation
Cannabis is propagated either from seed or from vegetative cuttings (clones). Seed propagation is the basis of all field-grown landrace and hemp cultivation and produces genetically variable populations. Clonal propagation produces uniform plants and is standard in commercial drug-type production.[1]
Vegetative growth
Vegetative growth occurs under long-day conditions or, in autoflowering types, on an internal clock. Plants establish root systems, leaves and structural branching during this phase. Topping and training are commonly used in commercial production to manipulate canopy structure and yield.
Flowering and pollination
In photoperiod-sensitive types, flowering begins as daylength decreases. Pollen is dispersed by wind and viable over distances of several kilometres, which makes pollen management central to drug-type cultivation aimed at sinsemilla and to seed-purity work in breeding programmes.[1] Identification and removal of male plants (roguing) is a routine field practice in sinsemilla cultivation.
Harvest
Fibre crops are harvested at or shortly before flowering, when stem fibre quality is at its peak. Seed crops are harvested at grain maturity. Drug-type harvests are timed to trichome development and inflorescence ripening, and may involve selective harvest of upper canopy first, followed by lower branches as they ripen.[1]
Post-harvest processing
Drug-type harvests are typically dried and cured to develop and stabilise their cannabinoid and terpene profiles before storage or further processing. Trimming removes non-resinous leaf material from inflorescences. Traditional resin extraction is treated under traditional processing, including hand-rubbed charas, sieve-pressed hashish, dry sift and bhang preparation.[1]
Fibre crops undergo retting and decortication. Seed crops are threshed and cleaned by methods common to other oilseed grains.
Breeding and selection
Traditional landrace cultivation relies on mass selection: farmers save seed in bulk from open-pollinated populations, with selection pressure exerted on the field as a whole rather than on individual lines.[4] Modern commercial drug-type breeding has shifted toward F1 hybrid production from cloned female parents and male pollen donors, a model that produces uniform crops but sits outside the population structure characteristic of landraces.[4][3]
Regional cultivation systems
Distinct regional traditions persist in cannabis cultivation, shaped by climate, end product, agronomic practice and history. Examples include:
- Hindu Kush cultivation, producing dry-sift hashish from short-statured drug-type populations across Afghanistan and northern Pakistan.
- Himalayan cultivation, including hand-rubbed charas traditions in Himachal Pradesh and Uttarakhand.
- Rif cultivation in northern Morocco, based historically on the kif landrace and producing dry-sift hashish, now subject to active introgression from imported hybrids.[11][12]
- Southeast Asian cultivation, particularly in Thailand and Laos, with tall narrow-leaflet drug types historically associated with the Thai stick trade.
- African cultivation across Southern and East African zones, with longstanding smallholder production for regional and export markets.
- Andean cultivation in parts of Colombia, Mexico and the broader Americas, the recipient of multiple introduction events and itself a source of widely traded seed material.[1]
Legal status
Cultivation is regulated by national, sub-national and international legal regimes. The 1961 Single Convention and subsequent treaties place drug-type cannabis under control, while fibre and seed-type cultivation is permitted in many jurisdictions subject to threshold limits on THC content.[2] Reform since the 2010s has produced varied national approaches, including legal medical and adult-use frameworks in parts of the Americas and Europe and licensed hemp sectors elsewhere. Eradication of unauthorised cultivation remains routine in many producing countries.[11]
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 Clarke, Robert C.; Merlin, Mark D. (2013). Cannabis: Evolution and Ethnobotany. Berkeley: University of California Press. ISBN 978-0-520-27048-0.
- ↑ 2.0 2.1 2.2 Small, Ernest; Cronquist, Arthur (1976). "A practical and natural taxonomy for Cannabis". Taxon. 25 (4): 405–435. doi:10.2307/1220524.
- ↑ 3.0 3.1 Chouvy, Pierre-Arnaud; Afsahi, Kenza (2014). "Hashish revival in Morocco". International Journal of Drug Policy. 25 (3): 416–423. doi:10.1016/j.drugpo.2014.01.001.
- ↑ 4.0 4.1 4.2 Casañas, Francesc; Simó, Joan; Casals, Joan; Prohens, Jaime (2017). "Toward an Evolved Concept of Landrace". Frontiers in Plant Science. 8: 145. doi:10.3389/fpls.2017.00145.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ↑ 5.0 5.1 Mills, Evan (2012). "The carbon footprint of indoor Cannabis production". Energy Policy. 46: 58–67. doi:10.1016/j.enpol.2012.03.023.
- ↑ 6.0 6.1 Dal Martello, Rita; Min, Rui; Stevens, Chris J.; Qin, Ling; Fuller, Dorian Q. (2024). "Morphometric approaches to Cannabis evolution and differentiation from archaeological sites: interpreting the archaeobotanical evidence from bronze age Haimenkou, Yunnan". Vegetation History and Archaeobotany. 33 (4): 503–518. doi:10.1007/s00334-023-00966-6.
- ↑ McPartland, John M.; Small, Ernest (2020). "A classification of endangered high-THC cannabis (Cannabis sativa subsp. indica) domesticates and their wild relatives". PhytoKeys. 144: 81–112. doi:10.3897/phytokeys.144.46700.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ↑ Lynch, Ryan C.; et al. (2025). "Domesticated cannabinoid synthases amid a wild mosaic cannabis pangenome". Nature. doi:10.1038/s41586-025-09065-0.
- ↑ 9.0 9.1 9.2 Balant, Manica; et al. (2025). "Integrating target capture with whole genome sequencing of recent and natural history collections to explain the phylogeography of wild-growing and cultivated cannabis". Plants, People, Planet. 7 (6): 1771–1788. doi:10.1002/ppp3.70043.
- ↑ Lapierre, Éliana; Monthony, Adrian S.; Torkamaneh, Davoud (2023). "Genomics-based taxonomy to clarify cannabis classification". Genome. 66 (8): 202–211. doi:10.1139/gen-2023-0005.
- ↑ 11.0 11.1 Chouvy, Pierre-Arnaud (2025). "Policy reform and the international future of Moroccan Cannabis production". International Journal of Drug Policy. 142: 104841. doi:10.1016/j.drugpo.2025.104841.
{{cite journal}}: CS1 maint: article number as page number (link) - ↑ Bachir, Fatima; El Oualidi, Jalal; Benkhnigue, Ouafa; Fekhaoui, Mohamed (2024). "Analysis of Morphological Traits in Herbarium of Historical Cannabis Specimens from Maghreb: Morphological Characteristics of Landrace Kif". Cannabis and Cannabinoid Research. 9 (5): e1395–e1403. doi:10.1089/can.2023.0102.