good flowering relies on a combination of factors.
but generally speaking, I ensure there is sufficient Calcium and Phosphate at onset of flowering and subsequently I make sure there is sufficient Potash for flowering.
but to my mind your question is too general to generate any meaningful answers.
i added bone meal and got dark green healthy leaves... cant say it improved bud quality cos buds were still green at harvest time. but i added it and i did see a difference.