Temperature Humidity Vpd

Temperature, humidity, and vapor pressure deficit (VPD) are environmental factors that significantly influence terpene expression in cannabis plants rather than terpenes themselves. VPD—the difference between air moisture saturation and actual moisture content—directly affects how plants regulate transpiration and volatile compound development. Breeders and cultivators recognize that terpene profiles vary substantially based on growing conditions; identical genetics can express different aromatic compounds under different environmental regimes. Optimal VPD ranges (typically 0.8–1.2 kPa during vegetative growth) are often associated with robust terpene synthesis, while stress from extreme VPD values may shift secondary metabolite production. Understanding these environmental-terpene relationships helps inform cultivation protocols within controlled genetics programs.

Breeders evaluating strain stability monitor how terpene expression responds to fluctuating temperature and humidity across growing cycles. Selecting for genotypes that maintain consistent aromatic profiles across environmental ranges is a key consideration in developing commercially reliable cultivars.