Grow Big Every-day

I had an issue of fungus gnats, in which I bought some Neem Oil to try and fix the situation. I given it a last soaking couple says later, seeing no signs of them,at leeway at the surface area. She is really small, and am not really sure why. I have made some mistakes I believe, like adding cal-mag on the beginning process, just used it, in her 1st nute feeding, this past Mon. Internodes sites are filling in nicely, only if the plant were bigger would it look presentable. Most of then have grown beyond the fan leaves to reach light. I have also given her a defoliation for better access to light and a little LST. Hairs are filling in as well, at the different but sites, just small at these sites.