Oh! I COMPLETELY forgot to mention that this year I cover cropped, and it made a HUGE difference in a whole bunch of things, especially keeping the soil moisture even and where cannabis likes it. I used a mix of clover, amaranth, fenugreek... and I think that's it. Yeah, I use a lot of fenugreek because it stays low to the ground and sets seed pretty quickly/easily, the greens are delicious and so is the seed, and it's easy to keep going. Bet the amaranth is, too, and it's very pretty when it gets big. Just make sure the seed heads are pointing AWAY from your girls!
I have that book. The problem for me is applying stuff like the row spacing, simply for the lay of our land and not having enough flat. That's where using permaculture principles can be far more helpful, creating edges, water sinks, etc.