4:20 is no longer considered the prime time of day to light up.

In fact, according to marijuana site DankGeek, only two states – Minnesota and Tennessee – are sticking to old traditions. Now, the times of day people like to smoke are all over the map (literally.)

You might remember how DankGeek used a software called Trendsmap to track geotagged Twitter data, specifically mentions of smoking, vaping, or consuming edibles, to determine how people liked to consume cannabis. These numbers were gathered from the same 150,000 tweets, instead observing the time of day when people were posting about their real-time marijuana use.

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Interestingly, a chunk of northern mountain region states like to smoke in the morning, even as early as 7:15 a.m. Smoking appears to be an after-work activity, falling between the hours of 5:20 p.m. and 9:40 p.m. for people in states where it’s recreationally legal, like California, Washington, Colorado and Michigan. The night owls, smoking as late as 11:50 p.m., are all over, namely in Utah, New Mexico, and Texas.

But where did the 4:20 tradition come from? Some say the origin was the date of a particular Grateful Dead concert, or police code for “Marijuana smoking in progress.” However, neither are correct – though the Dead lived just blocks from where this phrase actually came from.

It started at San Rafael High School in California in 1971, by a group of boisterous friends known as the Waldos. One autumn day, Waldo Steve received a treasure map to a patch of weed on the Point Reyes Peninsula. It was given to him by a friend’s brother who was growing cannabis. A U.S. Coast Guard, he was nervous about getting caught, so he said the only way the boys could harvest the weed was if they agreed to meet in front of the Louis Pasteur statue at 4:20 p.m.

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The Waldos set off to find the patch of weed, usually stopping to smoke beforehand. “420 Louie!” they called out to one another as they feverishly searched, day after day. Eventually, they just called it 420.

They never did find that mysterious patch, but now, 4:20 is considered a mainstay in cannabis culture.

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