There are a number of different elements that could be in fertilizer...including the 3 Macro-nutrients and the other elements and trace minerals...

Nitrogen in excessive amounts may delay flowering , but Phosphorus and Potassium )as contained in Bloom Boosters) will not impair flowering...

It's always best to try to encourage healthy beneficial micro-organisms by using well matured compost...encouraging beneficial fungi and mycorrhizal relationship with the roots including Mycorrization helper bacteria (MHB)...

Here are some threads where I addressed the topic previously...

http://forums.gardenweb.com/forums/load/vines/msg040710098176.html?2

http://forums.gardenweb.com/forums/load/vines/msg0212432810680.html

Heavy dosing with phosphorus will generally insure that phosphorus gets absorbed , but heavy phosphorus isn't good for the beneficial soil micro-organisms...

Give the soil the red worm test...if the worms will live in it ...that means it's likely good , but if the worms flee , then something is likely toxic or otherwise not right...

Hope the info in the linked threads helps...

TTY,...

Ron

Here is a link that might be useful: Beneficial micro-organisms for healthy living soil...