green dragon vs purple haze

green dragon

noun
  • A tincture of cannabis, typically made by soaking the flowers, leaves, or stems in ethyl alcohol. 

  • Used other than figuratively or idiomatically: see green, dragon. 

  • Any of several plants in the family Araceae, including the North American species Arisaema dracontium and the Asian genus Pinellia. 

purple haze

noun
  • One of numerous strains of cannabis known for their high THC content and recognizable by the color of their leaves, which vary from solid purple to flecked violet. 

  • lysergic acid diethylamide (LSD) when used as a recreational drug 

How often have the words green dragon and purple haze occurred in a corpus of books? (source: Google Ngram Viewer )