No one is exactly sure how April 20 became the day to celebrate marijuana, but with the legalization of recreational cannabis in 10 states, events surrounding the unofficial holiday are blowing up this year. Denver is offering grow tours, a cannabis-themed beer tour and a custom sushi-and-joint rolling class, while a 4/20 four-course pot-infused dinner party is taking place in Anaheim, Calif.
In states where cannabis is not yet legal, loosened-up federal regulations now allow wider use of CBD (cannabidiol), the nonpsychoactive component of marijuana. Although laws governing CBD differ in every state, some operators are using 4/20 as an excuse to play around with the hemp derivative.