When and how much B1?

So I found B1 really helps growing the root structure of these plants but when and how much? I've been using 1 tbl/gallon almost every watering (soil grow with Alaskan Fish Emulation also at 1 tbl per gallon)(B1 is the cheap Western States stuff found at Home Depot and the like for under $5 a gallon). Should I continue using it during flowering?

sure why not. cant see anything wrong with it, as long as you dont see any ill effects, which you shouldnt i would think. also i read that vitamin C was good for plants in general. i thought i read somewhere that vitamin B was only useful when used in conjuction with a particular other compound or vitamin (cant find the article) and was pretty much useless by itself. i could be wrong tho. if you have a link to where you read about B1

could you post it? i'd like to read it too. ive been curious about vitamins in general for cannabis. dont know why this didnt post in one section, musta hit a wrong button sorry.