I am however getting the master cannabis grower badge for myself and my dog at some point: https://www.reddit.com/r/PropagandaPosters/comments/7m522l/1940s_ussr_pin_awarded_to_farmers_for_master/

Someone there also expands on what you said:

Psychoactive Cannabis was also grown in the USSR as each republic was given jurisdiction over their drug laws. Most of the Middle Asia, Caucasian, and Alti regions of the USSR had been using psychoactive cannabis for centuries and continued to grow it for recreational uses. Though no where on the scale of Industrial Hemp (personal crops grown on personal property as any industrial production would be subject to the ban on the productions of recreational drugs) Psychoactive Cannabis was also grown and even given as a gift from Stalin to important individuals who would want to try it during their stay.

edit: I went searching for Stalin gifting psychoactive cannabis to people. I can only find this one anecdote where he may have given an ounce to Bukharin grown with fucking Lysenko's help:

They say that the weed grown in the USSR under Stalin was some of the most potent ever known to man. Under the guidance of Trofim Lysenko, Stalin assembled a crack team of growers whose marijuana was known for its intense body high and clarifying mental effects. In his personal diaries, Nikolai Bukharin writes, “Joseph [Stalin] came to me one night as I was struggling to finish the final edit of an issue of Pravda. He handed me an ounce of marijuana that reeked of skunk. The smell alone was enough to make me tremble. ‘This is a gift from Lysenko and I’ he said, and left almost immediately. I smoked that weed and I was never the same.”

Reefer Madness: A History of Marijuana, Larry “Ratso” Sloman, pg. 194

edit: That book has high amazon reviews and was written by a sociologist so I'm leaning more toward trustworthy source than non.