Phenotype Testing

Phenotype testing refers to the systematic evaluation of observable plant characteristics—morphology, terpene profile, cannabinoid ratios, flowering time, and growth patterns—to distinguish between genetically identical or similar cannabis plants grown under controlled conditions. Breeders and researchers use phenotype testing to identify which expressions of a given genotype are most stable, vigorous, or desirable for production goals. Testing typically involves growing multiple clones or seed-run plants from the same genetic line side-by-side, then documenting leaf shape, plant structure, resin production, aroma compounds, and yield metrics. Accurate phenotype documentation builds the breeding record necessary for selecting parent plants and stabilizing strain characteristics across generations. Phenotype testing is foundational to cannabis horticulture because genotype alone does not

Breeders rely on phenotype testing to select the most stable or vigorous expressions within a cross, establish breeding standards, and maintain strain consistency. Detailed phenotype records allow breeders to communicate accurately with cultivators about expected plant structure, flowering duration, and secondary metabolite profiles.