I like to mix some blood meal with the top 2 inches of soil so when I water it leeches some into it, I mix in blood or bone meal with the soil depending what stage they're at. What kind of Nutrients you using, Were pretty broke ass so we managed to get by for a while with wally world and CT specials such as MG all purpose for Veg. But we finally coughed up the dough to buy some advanced nutrients, micro nutrients because I found MG lack these, and some bloom food cause I didn't like the high N values found on common name brand stuff.
But like I was saying if you start practicing enriching your soil I find it easier to give em a little dash extra in a water solution later if need be, check out Subcool's Super soil recipe that's what I'm using from now on you just need pretty much half super soil and half normal soil and not have to feed em nothing but water from start to finish.