How Did 420 Become Associated With Cannabis Culture?

How did 4/20 the day, and 4:20 the time of day, become so emblematic of weed? The origin of the use of 420, celebrated around the world by pot smokers every April 20, has long been obscured by the clouded memories of the folks who made it a phenomenon.

Depending on who you ask, there are as many answers as strains of cannabis at your local weed dispensary. Some say it’s the number of active chemicals in marijuana. It’s teatime in Holland. It has something to do with Hitler’s birthday. It’s those numbers in that Bob Dylan song multiplied together.

The most credible story traces 4/20 to Marin County, California. In 1971, five students at San Rafael High School would meet at 4:20 p.m. by the campus’ statue of chemist Louis Pasteur to partake. They chose that specific time because extracurricular activities had usually ended by then. This group — Steve Capper, Dave Reddix, Jeffrey Noel, Larry Schwartz, and Mark Gravich — became known as the “Waldos” because they met at a wall. They would say “420” to each other as code for marijuana.

The shenanigans continued long after 4:20 p.m., too. The group challenged each other to find ever-more-interesting things to do under the influence, calling their adventures “safaris.”

Later, Reddix’s brother helped him get work with Grateful Dead bassist Phil Lesh as a roadie, so the band is said to have helped popularize the term “420.” On Dec. 28, 1990, a group of Deadheads in Oakland handed out flyers that invited people to smoke “420” on April 20 at 4:20 p.m. One ended up with Steve Bloom, a former reporter for High Times magazine, an authority on cannabis culture. The magazine printed the flyer in 1991 and continued to reference the number. Soon, it became known worldwide as code for marijuana. In 1998, the outlet acknowledged that the “Waldos” were the “inventors” of 420.

Bloom, now the publisher of Celebstoner.com, has credited the people who wrote the flyer for the date’s reputation as an annual gathering of pot smokers. “They wanted people all over the world to get together on one day each year and collectively smoke pot at the same time,” he wrote in 2015. “They birthed the idea of a stoner holiday, which April 20 has become.”