This study investigates the effects of Ascophyllum nodosum extract (ANE) on two high cannabinoid Cannabis sativa cultivars, CBD dominant ‘TJ’s CBD’ and ‘Wild Bourbon’. The experiment examined varying concentration levels, different application methods, and multiple application durations of ANE to assess impact on plant growth, yield, and cannabinoid concentrations. No prior research had been conducted on this specific area of study and results indicated significant effects in two parameters. Ratio of THC:CBD between the control and 2 ml/L drench application in cv. ‘TJ’s CBD’, and Average Flower Weight between 1 ml/L and 2 ml/L drench treatments for cv. ‘TJ’s CBD’. It is difficult to determine if ANE substantially influences cannabinoid responses due to the diverse combination of organic compounds found in ANE and the complex metabolic pathways of Cannabis secondary metabolites. Future research may explore different concentrations, treatment frequencies, and durations to better understand and optimize ANE in high cannabinoid cultivation of the Cannabis plant.