No nutes at first is a basic rule. I use a small dose of micros and some super plant tonic around the 2nd or 3rd watering. It just depends on the kind of soil I am using
the plant actually has a lot of nutrients stored in those two little round leaves that first appear... once those start to yellow it's safe to add nutrients... this happens between 2nd and 3rd week.
I used Bio-biz all mix and i didn't need nutes will begining of flowering. I was kinda worried at one point and added a bit of fertilizer at around 3/4 week veggin and it showed nute burn so i stopped.. soil does have a lot to do with it