Upstream Color (2013)
A man and woman are drawn together, entangled in the life cycle of an ageless organism. Identity becomes an illusion as they struggle to assemble the loose fragments of wrecked lives.
Orchids are, indeed, involved in the complex life cycle of the parasite:
At each stage of the worm-pig-orchid cycle there’s someone who profits from that stage and, unknowingly, advances the parasite to the next stage. The first person, whom the credits call the Thief (played by Thiago Martins), infects victims with the worm to brainwash them and steal their money. We see him do this to Kris, and we learn that he’s also done this to Jeff.
The second person, whom the credits call the Sampler (Andrew Sensenig), takes the worms from the Thief’s victims and puts them into pigs. The transfer of the worm establishes a connection between the victim and the pig, and the Sampler can then use the pigs to “sample” the victims’ experiences—each time he approaches a victim’s pig, he can see what’s going in that victim’s life. The Sampler is then inspired by these experiences to record music, which he sells through his record company, Quinoa Valley Rec. Co.
The third person, or actually the third group of people, are the two orchid farmers—the credits call them the Orchid Mother (Kathy Carruth) and the Orchid Daughter (Meredith Burke). When the Sampler disposes of pigs by bagging them and throwing them into a nearby stream, the parasite leaches out of the pigs and into white orchids, turning them blue. The two orchid farmers then pick these rare blue orchids and sell them through their company, E+P Exotics.
The Thief then buys these rare blue orchids—at the beginning of the film we can see that the flower pots he buys are labeled E+P Exotics—and uses the worms that come out of them, beginning the W-P-O cycle anew.
Found with a search for film orchids drug mind control
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