Perhaps this will help:

Horticultural Myths and Folklore
Rusty Trichome Reviewed by Rusty Trichome on . Plant Nutrient Nonsense After studying hundreds of product labels and reading several thousand posts, I am convinced that no one (even plant biologists and nutrition companies) have a clue about optimum NPK ratios other than the basic: More nitrogen in veg More phosphorous in flower Of course different plant species have different requirements, but beyond that the science is very slim and the only advice is 'cater to your plants' or 'buy our 10 products for maximum budding'. Doing a tiny non-comparative grow Rating: 5