You can find A black lotus behind the house on the left when you enter jade palace and walk toward the center. Or just hit the go to button and once you teleport, just go left to the back of the house. Then switch to a different realm for another in that same area. Switching realms makes farming for reagents a little quicker. There are also some locations in the area to the right of shonun village. what's it called, it has a cave and krakens that walk on all fours. You can find lotus there. but not inside the cave. The areas around it.
also, i presume you have access to the floating land? by the living waterfall, there is a loop that goes around to the downed blimp, so here is how you do the route, you go to the blimp by the teleporter, and you take the right path down to the waterfall, you need to "hug" the right edge and walk the route, you will get a bunch of lotus if you take that route and switch realms every time you get to the start of the dirt path
Usually i go to the Cave of Solitude in Mooshu and go to the 4 dead ends at the bottom of the map and run a route that goes from one of the end dead ends to the other end dead ends and go to the two between. It is kind of a long run but it totally works!