Unraveling the Confusion of Flowering Types and Terminology in Cannabis sativa

Cannabis ( Cannabis sativa ) is a dioecious plant with many flower types. Academia currently uses multiple definitions of cannabis flowering that inadequately capture the diversity that occurs in variable temperatures and photoperiods. This perspective article reviews the imprecise flowering terminology that has created contradictions in research findings and confused the photoperiodic classification of cannabis. We describe new terminology to differentiate between two types of female reproductive structures with subclassifications for specific female flower appearances. “Botanical pistillate flowering” refers to the day-neutral single pistillate flowers that appear at the nodes of female and monoecious plants. “Commercial pistillate flowering” leads to a distinctive compound inflorescence and is marked by the appearance of a domed structure with three stigma pairs on the dominant growing point in female and monoecious plants. Female flowering can be further described as “early - or late-stage incomplete commercial pistillate flowering.” Male reproductive structures develop into two forms. “Botanical staminate flowering” produces panicles with bell-shaped pedicellate flowers that have five petals, which open to reveal five anthers attached via anther filaments in male and monoecious plants. “Antheral flowering” is characterized by the appearance of single anthers or clusters of anthers that lack a pedicel and have no petals or filaments at the nodes or within the female inflorescence on monoecious plants. We include descriptive examples and photographs to facilitate the adoption of precise flowering terminology.