Home cultivation across Canadian provinces after cannabis legalization

Abstract

1. Introduction

On October 17, 2018, Canada became the second country in the world to legalize non-medical cannabis (Government of Canada, 2018). Briefly, the Cannabis Act permits adults aged 18 and over to purchase cannabis, cultivate up to four plants, and possess up to 30 g of dried flower (or equivalent, e.g., 30 cannabis seeds) in public (Government of Canada, 2018). Canadians can access legal non-medical cannabis through physical and online retail stores, sharing small amounts among friends and family, or growing personal cannabis plants (home cultivation).

Prior to the legalization of non-medical cannabis in 2018, home cultivation was permitted for consumers with medical authorization under certain conditions (Fischer et al., 2015, Government of Canada, 2016). Those with medical authorization were permitted to grow their own cannabis; or designate someone to grow cannabis on their behalf (Fischer et al., 2015, Walsh et al., 2013). In October 2018; immediately prior to legalization of non-medical cannabis, less than 1% of Canadians were registered with Health Canada for medical cannabis and 7.5% of Canadians with medical authorization had an active registration to grow or designate someone to grow on their behalf (Government of Canada, 2020, Statistics Canada, 2021). In October 2020; approximately two years after non-medical legalization, this percentage had risen to 11.3% (Government of Canada, 2020).

Under the Cannabis Act, unchanged from the preceding “Access to Cannabis for Medical Purposes” regulations, the number of plants grown for medical consumption is determined by the daily quantity of cannabis outlined in the patient’s medical authorization (Government of Canada, 2016, Government of Canada, 2021). In general, for every gram of dried flower authorized, five plants are permitted indoors or two outdoors (Government of Canada, 2016, Government of Canada, 2021). For instance, if the patient is authorized two grams of dried flower per day, ten plants would be permitted indoors. Therefore, Canadians growing for medical purposes may have higher limits of the number of plants grown than Canadians growing for non-medical purposes (four plant limit) (Canadian Centre on Substance Use and Addiction, 2020). Moreover, provinces and territories have jurisdiction on retail sales and distribution, including prohibiting home cultivation, and so regulations vary across the country (Canadian Centre on Substance Use and Addiction, 2020). For example, Manitoba and Quebec prohibit home cultivation of non-medical cannabis, whereas all other provinces allow up to four plants (Canadian Centre on Substance Use and Addiction, 2020).

In a legal market, allowing residents to grow their own cannabis at home provides a relatively low-cost source of cannabis for those who prefer not to purchase from retail stores or pay taxes, to have more control over cannabis strains, or for those growing for enjoyment (Caulkins et al., 2016, Transform Drugs Policy Foundation, 2016, Government of Canada, 2016). Indeed, home cultivation could support the objectives of the Cannabis Act, if those growing a personal supply are doing so instead of sourcing illegally (Caulkins et al., 2016, Transform Drugs Policy Foundation, 2016). Conversely, home cultivation has the potential to undermine objectives of the Cannabis Act, which include reducing the illegal market and prevent underage consumption (Government of Canada, 2018). Home cultivation could provide easier access to children in the home, allow opportunity for illegal resale, and avoid the strict regulations that were created to protect public health (Azofeifa et al., 2021, Government of Canada, 2018). Further research is needed on home cultivation in Canada since legalization, including who grows their own cannabis plants.

When compared to other supply sources such as friends and family or retail stores, home cultivation rates have been found to be comparably modest, both before and after legalization (Government of Canada, 2017, Rotermann, 2021). In the National Cannabis Survey; 8.0% of past three-month cannabis consumers reported getting their cannabis by growing their own or someone growing it for them before legalization in the first quarter of 2018 (Rotermann, 2021). In the first quarter of 2019; 9.0% reported past three-month home cultivation, which significantly increased to 14.2% in the fourth quarter of 2020 (Rotermann, 2021). Similar percentages of home cultivation were found in the Canadian Cannabis Survey among past 12-month consumers: 5.6% reported growing their own cannabis before legalization in 2018; compared to 9.0% and 15.3% after legalization in 2019 and 2020, respectively (Government of Canada, 2019, Government of Canada, 2017, Government of Canada, 2018, Government of Canada, 2020, Government of Canada, 2020). In 2020; the Canadian Cannabis Survey also reported home cultivation among Canadians who were not cannabis consumers in the past 12-months: 3.3% of non-consumers reported home cultivation in the home in 2020 (Government of Canada, 2020). However; neither survey examined how home cultivation varies by cultivation policies.

Previous research conducted in the United States (U.S.) examined individual and U.S. state characteristics associated with home cultivation (Azofeifa et al., 2021, Borodovsky and Budney, 2017, Nguyen et al., 2015). In a study examining individual characteristics of home cultivation among U.S. adults, approximately 2% of past-year consumers aged 21 and older reported growing cannabis between 2010 and 2014 (Azofeifa et al., 2021). Growing cannabis was significantly higher among males, those living in rural areas, and more frequent cannabis consumers. Three studies conducted in the U.S. examined the association between state legislation and home cultivation rates (Azofeifa et al., 2021, Borodovsky and Budney, 2017, Nguyen et al., 2015). In general, states with more permissive cannabis laws (e.g., medical cannabis laws, permitting home cultivation) had higher rates of respondents growing their own cannabis, demonstrating the impact of policy on individuals’ propensity to grow cannabis at home. To our knowledge, there is no research to date on the variation of home cultivation rates across the provinces in Canada after legalization.

Research on non-medical home cultivation in Canada since non-medical cannabis legalization is nascent. To our knowledge, the current study is among the first to examine provincial policies and home cultivation among Canadians since legalization. The aims of the study were to: (1) estimate the percentage of Canadians who reported growing cannabis plants in 2019 and 2020 as well as past 12-month cannabis consumers who reported growing cannabis plants in 2018, 2019, and 2020; (2) estimate the quantity of plants and expenditure of cannabis plants/seeds; and (3) examine the association between provincial policies, cannabis use status, and home cultivation in 2019 and 2020.

2. Methods

Data are from Waves 1–3 of the International Cannabis Policy Study (ICPS), repeat cross-sectional surveys conducted in Canada and the U.S. Data were collected via self-completed web-based surveys before legalization in August-October 2018, and after legalization in September-October in 2019 and 2020 from respondents aged 16–65. A non-probability sample of respondents was recruited through the Nielsen Consumer Insights Global Panel and their partners’ panels. For the ICPS surveys, Nielsen draws stratified random samples from the online panels, with quotas based on age and state/province of residence. Nielsen emails panelists an invitation to access the ICPS survey via a hyperlink; respondents are unaware of the survey topic prior to accessing the link. Respondents confirm their eligibility and provide consent before completing the survey. Upon completion, respondents are transferred back to the Nielsen platform and receive remuneration in accordance with their panel’s usual incentive structure. Monetary incentives have been shown to increase response rates and decrease response bias in subgroups under-represented in surveys, including disadvantaged subgroups (Groves et al., 2009).

Surveys were conducted in English or French. Median survey time was 20 min in 2018, 25 min in 2019, and 21 min in 2020. Data integrity measures include checks for ‘speeders’ based on completion times, the quality of open-ended responses, patterns of ‘Don’t Know/Refusal’ responses, and inconsistent responses across items (American Association of Public Opinion Research (AAPOR), 2018).

The current study reports data from the Canadian sample only. In 2018, 17,157 Canadian respondents accessed the survey link, of whom 10,646 completed the entire survey for an AAPOR cooperation rate of 62% (American Association for Public Opinion Research, 2016). In 2019, 24,607 respondents accessed the survey link, of whom 17,513 completed the entire survey (63%) and in 2020, 25,827 respondents accessed the survey link, of whom 17,001 completed the entire survey (66%) (American Association for Public Opinion Research, 2016).

The study was reviewed by and received ethics clearance through a University of Waterloo Research Ethics Committee (ORE#31330). A full description of the study methods can be found in the ICPS Technical Reports and methodology paper (Goodman and Hammond, 2019, Goodman et al., 2020a, Goodman et al., 2020b, Hammond et al., 2020).

3. Results

Table 1 displays the unweighted and weighted sample characteristics of respondents in 2019 and 2020. Supplemental Table 1 displays the unweighted and weighted sample characteristics of past 12-month cannabis consumers in 2018, 2019, and 2020. For both samples, half of respondents were male, and three-quarters were white.

4. Discussion

Home cultivation among past 12-month cannabis consumers increased to a modest extent following legalization of non-medical cannabis in Canada, from approximately 6% in 2018, to 8% and 9% in 2019 and 2020. Similar estimates of home cultivation were found in the Canadian Cannabis Survey; however, the percentage of home cultivation in 2020 was slightly higher than the current study (15.3% vs 8.8%) (Government of Canada, 2019, Government of Canada, 2017, Government of Canada, 2018, Government of Canada, 2020, Government of Canada, 2020). This is potentially due to a change of question in the Canadian Cannabis Survey from 2019 to 2020 (Government of Canada, 2019, Government of Canada, 2020). In 2020, the Canadian Cannabis Survey asked for plants grown within respondents’ home, not necessarily grown by the respondents themselves, i.e., a family member. The current study only asked about personal home cultivation.

The majority of growers appear to have abided to the non-medical limit of four plants after legalization. In 2020, three-quarters of consumers grew four plants or less in the past 12-months, compared to only half in 2018. Indeed, the median number of plants grown in the past 12-months in 2020 was 3.3, similar to what was found in the 2020 Canadian Cannabis Survey (3.0) (Government of Canada, 2020). These results suggest that four plants is a realistic limit for the majority of growers, and that perhaps those that grew prior to legalization had either a higher limit of plants due to medical authorization, or no limit, as their activities were illegal. In addition, it could reflect a reduced need to grow higher quantities, given the widespread availability of legal sources. Future research should explore the reasons for growing and whether home cultivation reduces access to the illegal market.

Home cultivation rates were lower in provinces that prohibited home cultivation, namely Manitoba and Quebec. These results complement research from the U.S., where consumers in states with more restrictive cannabis policies were less likely to report growing cannabis plants (Azofeifa et al., 2021, Borodovsky and Budney, 2017). Notably, the prohibition of non-medical home cultivation in Quebec and Manitoba is being challenged. If these laws are overturned, these provinces may see an increase in home cultivation (Brown, 2021).

Ontario, Nova Scotia, New Brunswick, and British Columbia had the highest rates of home cultivation in 2019 and 2020. A potential explanation is access or the price of legal cannabis, where low access and high prices may encourage cultivation. For example, Ontario was slower to open legal ‘brick and mortar’ stores than other provinces: the first store opened six months after legalization. Two years after legalization, in September 2020, Ontario still had only 112 stores (0.9 stores per 100,000 residents aged 15 and over). However, after the current data collection in September 2021, Ontario had 1042 stores (8.3 stores per 100,000 residents aged 15 and over) (Alcohol and Gaming Commission of Ontario, 2021, Statistics Canada, 2021). As Ontario increases their number of stores, greater accessibility and lower prices in the legal market may reduce incentive to grow your own plants; therefore, we may see further changes to home cultivation rates past the current study period. Moreover, if consumers were growing plants for sale, the greater availability of legal cannabis is likely to reduce the demand for illegal cannabis. Quebec, the province with the lowest rates of home cultivation, also had a low number of stores per 100,000 residents in 2019 and 2020; however, Quebec also reported some of the cheapest average dried flower prices across the provinces (Mahamad et al., 2020, Martin, 2019, Wadsworth et al., 2020). It is possible that retail structure (i.e., private, public, hybrid) could influence home cultivation rates; however, evidence of this was not found in the current study. Future research should continue to examine the rates of home cultivation by province and retail structure over the years.

Location may determine whether Canadians grow their own cannabis plants. Canadians residing in rural locations had higher odds of home cultivation. Similarly, in a study among U.S. cannabis consumers, higher rates of home cultivation were found among those living in rural areas of the U.S (Azofeifa et al., 2021). It may suggest that Canadians residing in rural areas may have more land and space to grow, further from retail stores, or comfort to grow undetected or without disturbing neighbours. Indeed, respondents living in smaller living spaces in urban settings may be further influenced by restrictions on home cultivation in rented accommodation or shared living spaces (Government of Alberta, 2021, Nanowski, 2018).

A strength of the current study is its inclusion of both consumers and non-consumers (i.e., those who had not consumed within the past 12-months or ever). Previous research focuses on cannabis consumers, where more frequent cannabis consumers have higher rates of home cultivation than infrequent consumers, as seen in the current study (Azofeifa et al., 2021, Potter et al., 2015). However, non-consumers also grow cannabis plants either for sharing or sale, and therefore should be included in research. The Canadian Cannabis Survey included non-consumers in their 2020 study; however, the survey did not specify personal cultivation by non-consumers, i.e., non-consumers could report home cultivation in their home by others (Government of Canada, 2020). Future research should capture non-consumers in studies around home cultivation and examine the reasons for growing.

Role of funding source

Funding for this study was provided by a Canadian Institutes of Health Research Project Bridge Grant (PJT-153342) and a Canadian Institutes of Health Research Project Grant. Additional support was provided by a Public Health Agency of Canada-Canadian Institutes of Health Research Chair in Applied Public Health (DH) and a Mitacs Elevate Postdoctoral Fellowship in partnership with the University of Waterloo and the Canadian Centre for Substance Use and Addiction (EW). The funders had no role in study design, collection, analysis or interpretation of the data, report writing, or decision to submit the report for publication.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

Footnotes

References