Field observations: Photoperiod response and yield of hemp at various latitudes throughout New Mexico

Abstract There has been a rapid increase in research to understand the genetic and agroclimatic interactions of hemp ( Cannabis sativa L.) relative to its economic viability. Initial field trials at New Mexico State University were conducted in 2021 and 2022 at three sites across the state for high‐cannabidiol (CBD), grain, and fiber hemp types. The goal of this work was preliminary evaluation of factors, such as variety choice and production conditions (specifically, water stress and organic management), to highlight topics that should be studied in full variety trials. Even with the limited scope, two important lessons from the studies are expected to be valuable for the developing industry: (a) the majority of available, compliant industrial (grain/fiber) varieties show severely shortened vegetative phases and early reproductive responses at low latitudes; and (b) high‐CBD varieties perform inconsistently in outdoor production, rarely producing flower biomass yields and total CBD content necessary for economic viability. Future work is needed in the southwestern United States to find grain/fiber varieties with genetics suitable to the latitude and to reduce the costs of indoor production of CBD varieties.