partial sun should be enough

you didnt mention whether its planted in ground or in a pot.

also, how much and how often do you fertilize?

It is in a pot. I have only given it slow release fertilizer. I don't know anything about tropicals as they differ from other plants. Do I need to do the slow release more often than once per season?

Tropicals are not really that different that different from other plants in my opinion. But getting back to your concern, I have yet had Strelizia reginae bloom for me despite having grown them for years! I would ease off though on any fertilizing and also reduce watering. Plants often respond to drought by entering a flowering period. If you think about it from the plant
perspective, severe drought means I might die so I better produce flowers and seed to endure the dry season in order to survive once the rains return. Good luck and post pics if they do bloom.

Hi
Have grown all three types but only as yard plants . As I recall it took the orange variety around 4/5 years to start but has been flowering since. It is located in full blazing sun , in the ground. gary