Temporal cannabinoids profile and biomass yield in cannabigerol dominant industrial hemp under different planting dates in southern Florida

Industrial hemp (Cannabis sativa L.) commercialization in Florida is mainly challenged by the lack of suitable essential oil hemp cultivars with Delta-9-tetrahydrocannabinol (THC) concentration below the legal threshold. However, previous studies have only evaluated cannabidiol (CBD)-dominant industrial hemp cultivars but not the cultivars primarily grown for cannabigerol (CBG) production. Hence, field trials were conducted using two CBG dominant cultivars adapted in Kentucky (CBG Gold) and Colorado (Panacea) at three experimental farms located at Okeechobee (Lykes) and Clewiston (Townsite and Ritta) in southern Florida with three planting dates from late April to late June under two different soil types (sandy soil at Lykes and Townsite, and organic soil at Ritta). CBG, CBD, and THC concentrations were analyzed in developing flowers harvested at weekly intervals beginning 2 weeks after flowering until crop maturity. Location and planting date had some effect on cannabinoids profile, but the effect was not consistent in any of the tested cultivars. Both the cultivars contained THC concentration (<0.1%) well below the legal requirement making them suitable for cultivation in Florida. However, both the cultivars adapted in longer photoperiod environments recorded short vegetative growth period in Florida's short-day conditions and consequently produced less floral biomass. Hence, evaluating more cultivars with shorter photoperiod requirements would be helpful in identifying suitable CBG-dominant cultivars for Florida and other locations with similar climatic conditions.