PK booster for big plants in ground?

For organic PK booster you might wanna try Bac PK boosterb maybe some biobizz top max or some guanos, kelp (dry or liquid) or even banana tea :)

Have a look at my huge girls. Their all fed Massive Bloom Formulation. I swear by this stuff. All natural, made from bees. Best I have found since I started to use bloom boosters. Did a clone side by side comparison to no booster, the plant with massive bloom formulation, through out an ounce and a half more than her sister, with bigger harder nugs, and the girl with the booster tasted much nicer than without. Cheers

Yep Bro, you can add PK nutes in the irrigating water. Looking at you plants they seem to have all they need. IMO you are doing well and balanced until now.When the plant will need something she will be the one to tell you, yellowing and discoloring the bottom canopy (which in any case would turn yellow due to senescence). Balance is the trick! Balance is the trick!