Phytochemical Ratios

Phytochemical ratios refer to the proportional relationships between cannabis plant compounds—primarily cannabinoids like THC and CBD, alongside secondary metabolites such as terpenes and flavonoids. Breeders track these ratios because they influence the plant's chemical profile independent of absolute potency levels. A strain might express a 1:1 THC:CBD ratio, a dominant CBD expression with minor cannabinoids, or complex terpene hierarchies that vary across phenotypes. Understanding ratios requires laboratory testing, as visual inspection cannot determine actual compound concentrations. Lineage records frequently report ratio tendencies, though environmental factors and harvest timing significantly affect final expression. Ratios serve as a foundational tool for breeding strategies targeting specific phytochemical outcomes.

Breeders working in this category select parent plants and offspring based on consistent phytochemical ratio expression across generations. Stabilizing desired ratios—whether cannabinoid-forward, balanced, or minor-cannabinoid-enriched—requires multi-generational selection and test-crosses to identify genetically reliable phenotypes.