... Their formula was 8-8-20. My plants loved this formula. ... I believe high amounts of soluable potassium are much more important during bloom than phosphorus or nitrogen for that matter. My work with tropical fruit trees seems to confirm this. Just my personal opinion.
i am trying this with ej line of ferts. i love ejThis year I am going to experiment with switching from high P/K throughout bloom, to high P in early flower, to high K in late flower.
KOG has a video on youtube where he feeds his outdoor plants ashes (high K) a month before harvests, which gets him bigger heads.
So maybe that is the way to go - and the answer to preventing P buildup in the soil in flowering.