You just forgot what you have to achieve (lvl, stats, talents, quests done and so on) to unlock the scene where Katherine teaches you how to craft them.
Same with filling vials.
Don't ask me because I don't remember. Just keep playing and you'll find it out, sooner or later.
What are the requirements for filling vials with water?
I can make armor+energy potions, and get all the ingredients. But I can't get water.
My only guess, is I need to do the farmer girls quest to unlock "gathering water" for the vegetables.
Now, I really hope not. That would be really dumb.
In game it told Me (tooltip? Katherine? Forgot), i can get water from the troths at the training ground. It told me this after I got 5 nature and asked about herbalism.
And when I unlocked the nature skill in thr first place. Katherin said I have the recipe necessay to find and gather plants and create the needed mixture(I had no idea it was healing tinctures until after I went back to rumah, and was told explicitly. The MC knew what I hadn't been told.).
And I'm not going to stop playing cause of this. I was just hoping for a solution or answer.
Certainly better than just pretending I'm an idiot when you don't even know what you're talking about, whether I'm right or wrong. (And you don't, cause you don't know the answer.)
Maybe jump off that horse?