After ACT decriminalized small-scale cannabis cultivation, home-grown samples averaged 9% THC — moderate potency — with few contaminants, though 52% of growers remained anxious about arrest due to legislative grey areas.
Policymakers considering cultivation laws, home growers, harm reduction advocates, and cannabis policy researchers.
What the researchers found
311 ACT growers cultivated a median of 4 plants/year, consumed a median of 1g per use day. Cannabis samples (n=71) had moderate THC (mean 8.99%), low CBD (<0.1%), and few contaminants. Growers cited self-supply and avoiding criminal networks as primary motivations, but legislative ambiguities created ongoing legal anxiety.
Why it matters
This is rare real-world data on what happens when small-scale cultivation is decriminalized. The moderate potency and low contamination suggest home growing may produce safer products than black market supply.
The numbers in context
311 growers surveyed. Median 4 plants/year, 1g per use day. 71 samples analyzed: mean THC 8.99% (±0.51), CBD <0.1%. Few exceeded contaminant guidelines. 52% remained anxious about arrest.
How the study worked
Cross-sectional online survey of 311 current and past cannabis cultivators in Australia's Capital Territory plus phytocannabinoid and contaminant analysis of 71 home-grown cannabis samples.
What this study cannot tell us
Self-selected sample may over-represent engaged growers. ACT-specific legal framework may not generalize. Voluntary sample submission may bias toward better-quality cannabis.
How to read the evidence
Unique real-world data combining survey and chemical analysis, but self-selected sample and single jurisdiction limit generalizability.
When this study was published
Recent study examining outcomes of the ACT's 2020 cannabis decriminalization — among the first to analyze home-grown cannabis in a decriminalized setting.
The bigger picture
Home cultivation is allowed in several jurisdictions but rarely studied. This data shows decriminalization largely works as intended — people grow for personal use, avoid criminal markets, and produce reasonably safe products — but legislative clarity matters.
Questions still open
- Does home cultivation actually reduce demand from criminal markets? Should decriminalization laws provide clearer guidance to reduce ongoing legal anxiety among growers?
Common questions
Is home-grown cannabis safe?
Why are growers still anxious about arrest?
Read the original research
An analysis of the cultivation, consumption and composition of home-grown cannabis following decriminalisation in the Australian Capital Territory.
Scientific reports, 15(1), 2649
Citation
Zhou, Cilla; Lavender, Isobel; Gordon, Rebecca; McCartney, Danielle; Kevin, Richard C; Bedoya-Pérez, Miguel A; McGregor, Iain S. (2025). An analysis of the cultivation, consumption and composition of home-grown cannabis following decriminalisation in the Australian Capital Territory.. Scientific reports, 15(1), 2649. https://doi.org/10.1038/s41598-024-84897-w