In my experience, yes, you’ll need to add some. I’ve been using dry amendments lately, adding around week three with the expectation that the good stuff will start getting to the roots around week 4. They’re often moving into full flower by week four or five, and the demands will increase/change accordingly. Go light initially if using liquid nutes. I’ve had poor luck with the ff liquid trio, though I’ve been growing in ffof for several grows. Aside from the gnats that came in the summer bags, great stuff.
As mentioned above, look at
@Budzbuddha