PURPLE AND BLUE CANNABIS STRAINS Purple and blue marijuana strains are fast becoming very popular amongst growers & smokers alike. The growing popularity of these colors has become a mainstay in dispensaries with customers opting for the attractive buds. Purple and blue marijuana strains turn color as a result of seasonal changes in temperature, however they also require specific genetics to change to the highly coveted purple and blue hues. Look through our list of purple and blue marijuana strains below - we're sure you’ll find something you like!