lol yep... not only nitrogen, either

ferts have 3 numbers, corresponding to an n-p-k ratio - nitrogen phosphorus and potassium

you want a fert that is high in n for now, but a week or 2 after you switch the lights to flowering, you want ferts that are high in p and k

and for the last 2 weeks, no ferts at all, plain water to wash the ferts away, fan leaves will yellow off at this point, completely normal - this means the plant is using nutes from its vegetation, and not the soil, flushing all those excess nutes out of the soil/plant will make your end result smoother and tastier :thumbsup:

i would suggest fox farms grow big for now and big bloom for flowering, or earth juice grow and bloom... stick to the organics if ya can, the better the food, the better results