Is passing the plant possible? and What do I mix in the elven beer to knock out the orc?
You need to mix the plant with the elven beer. To do that, cut off the plant with the shears.
To get the shears, first, go to the Minotaur area, then go through the wooden gate in the background, it should get you to the area with the feather girl. There are shears to the right of where you "spawn".