Relative Humidity Cultivation

Relative humidity (RH) during cultivation is an environmental parameter that significantly influences cannabis plant physiology and secondary metabolite expression, including terpene profiles and resin development. Breeders and cultivators working within controlled environments have long recognized that RH levels—typically maintained between 40–70% depending on growth stage—affect how plants express aromatic compounds and structural traits. While genetics determine the baseline terpene blueprint, environmental RH can influence the volatility, concentration, and perceived character of aromas during growth and at harvest. This relationship between environment and expression is central to understanding phenotypic variation within stable genetic lines. Documentation of cultivation conditions, including RH ranges, helps breeders isolate genetic from environmental factors when selecting for st

Breeders track RH conditions during seed production and phenotype evaluation to ensure consistent expression of target aromatic traits and to distinguish true genetic variation from environmentally induced phenotype drift. Standardized RH documentation in breeding trials supports reproducibility and informed parent selection for aroma-focused crosses.