Where did Arthur get red flowers from?

We see red flowers in Arthur's house, Egg observation room, and the house in Grasstown. With the former two it's understood that they were procured by Arthur and Igor respectively to gain the power needed to protect what was important to them, while with the one in Grasstown it's a little less clear. I'm curious about where they all found red flowers, and when exactly. I'd assume after the war 10 years ago? Considering Arthur was only recently killed, and we don't really hear anything about his involvement in that war itself. But hasn't Jenka kept the flowers strictly guarded since then? How did these actors get their paws on it? Idk something to thing about.

 

Perhaps Arthur during the war got his hands on the flowers to maybe help the effort? No idea how Igor got them though, maybe the man Igor stayed with acquired them to research and then he died and Igor ate the flowers.

 

Always found them to be one of the more quietly unnerving unexplained background elements. Once it came to light that King had experimented with the flowers it occurred to me that maybe it'd actually been him messing around in the basement. I don't remember any mention that Arthur ever used/needed them and regardless it always seemed weird that he would've just left them laying around there where someone like Toroko could find them.