Cold Color Phenotype

Cold color phenotypes in cannabis refer to plants expressing purple, blue, or dark violet hues in foliage and flowers, typically triggered by anthocyanin pigment expression under cooler temperatures or specific genetic conditions. These colorations are distinct from chlorophyll and emerge most prominently during late-stage flowering when night temperatures drop, though some genetics display cold colors regardless of environmental conditions. Cold color expression is often associated with specific terpene profiles and has become a breeding focus in recent decades, particularly within indica-leaning and hybrid lineages. The trait is genetically heritable but phenotypically variable, meaning identical genetics may or may not express cold colors depending on cultivation environment. Breeders working with cold color phenotypes typically maintain detailed records of temperature thresholds and

Cold color phenotypes serve as visual markers for lineage tracking and phenotype selection in breeding programs. Cultivators and breeders often use cold color expression as an indicator of genetic stability and as a tool for creating marketable plant diversity within established strain families.