They do. Many years ago (1989) there was a drama on Channel 4 called Traffik. It was the story of struggling and poor farmers, to addiction to heroin and it’s ugliness in the western world.
Coincided with an unknowing local farmer at a place just up the road from us decided to go the green route and not use herbicides on his fields. Turns out that some of his south facing fields were used to produce opium and morphine for use as painkillers during WW2. Of course the long lasting seed loved this and instead of wheat he ended up with fields of multicoloured flowers. We were camping nearby and cut a lot of poppy heads one sunny morning and went back at the end of the day to get a little bit of dried sap. I don‘t know the legality of it, but it is possible. For what it’s worth it made us puke a lot.
