Dr. Greenthumb is a 1998 single by Cypress Hill. The song is about B-Real telling a story about his alter-ego Dr. Greenthumb, a cannabis/marijuana grower. A music video was also released. The name “Dr. Greenthumb” was later used in Tell Me When to Go by E-40. The name Dr. Greenthumb dates back to the 1970s cartoon “Josie and the Pussycats,” where the name referred to a villain who ruled “creature plants.” It is unclear if this title was lifted by Cypress Hill.