The use of specific cultivation practices, in parallel with a shift toward indoor cannabis cultivation, has likely contributed to increasing cannabis herb potency, notably in industrialized countries. These developments, alongside an ever-broader variety of cannabis products, are likely being fueled by market competition in legalized and illegal settings, and interaction across those settings.

• Data reported by Member States suggests indoor cultivation has expanded faster than outdoor cultivation over the past decade and is now encountered across all regions of the world, although outdoor cultivation still dominates in many countries outside Europe.
• This shift has also enabled a number of countries to cultivate cannabis where climatic conditions are unsuitable for outdoor production. In parallel, controlled indoor environments, specific cultivation practices such as removing male plants or using feminized seeds in order to prevent pollination, and improved plant varieties have enabled higher THC levels.
• Rising potency – particularly in North America and Europe – has been associated with heavier consumption and risks for cannabis use disorders, notably among young adults and have contributed to a growing demand for cannabis-related treatment services. Falling levels of CBD may have also played a role.
• Growing indoor cultivation and growing levels of THC in cannabis herb may also have impacted global cannabis herb trafficking flows, with high-THC products from North America increasingly reaching overseas markets.