Hemp (Cannabis sativa <0.3% tetrahydrocannabinol, THC) is a multipurpose crop that has garnered much public interest in recent years. While hemp was once one of the most widely grown crops, decades of prohibition during the last century have hampered critical research and supply chain development that would make hemp a viable crop. Interest from academics, government, and industry has grown with the recent legalization of hemp, but research on the crop still lags behind. In this dissertation, I will present research conducted to characterize the variation in, and genetic basis of, several key horticultural, agronomic, and biochemical traits for hemp production. First, I will present an experiment designed to characterize variation in cannabinoid accumulation, flowering time, growth rates, and powdery mildew susceptibility among high-CBD hemp cultivars. Then, I will present an experiment designed to characterize variation in high-CBD hemp plant architecture and the relationship among plant architecture, the distribution on biomass within the plant canopy, and intra-plant variation in cannabinoid concentration. In the two chapters on biotic interactions, I will present an experiment characterizing the genetic basis of a new source of powdery mildew resistance in hemp, followed by a series of experiments investigating the functional role of cannabinoids in defense against chewing herbivores. Extensions of this work are discussed, some of which have been or are actively being pursued by the Cornell Hemp research group.