Purple Phenotypes

Purple phenotypes in cannabis refer to cultivars expressing anthocyanin pigments, which create violet, deep red, or burgundy coloration in flowers and foliage. These pigments are distinct from chlorophyll and emerge under specific environmental conditions—typically cooler temperatures during flowering and genetic predisposition. Purple coloration does not indicate cannabinoid or terpene content; it is a visual trait controlled by multiple genes and environmental triggers. Breeders have selectively worked with purple-expressing lineages for decades, though the trait remains inconsistently expressed across generations. Documentation of purple phenotypes appears in classic cultivar families like Purple Haze and Grandpa's Stash, though commercial stability varies significantly.

Breeders pursuing purple phenotypes typically employ line-crossing and phenotype selection to stabilize anthocyanin expression, though environmental manipulation (cold exposure) remains necessary for reliable color development in many lines. Purple traits are often combined with other characteristics in breeding programs, making it a secondary rather than primary selection criterion in most commer