I read from somewhere that bougs like to be root bounded in order to flower prolifically.

In his site, GORDON BRASWELL said: "A bougainvillea blooms best when pot-bound. So, do not be tempted to repot unless you must. I have found that it is best to leave the plant in its original container until the roots have replaced all of the soil and you can't keep the plant well watered. For example, it is not unusal to grow a bougainvillea in a 1-gallon pot for 3 or more years."

He also mentioned feeding is essential for a healthy growth but do not over feed the plant.

The most important info is here:

"Bougainvillea has two distint growth cycles:
A vegetative growth period for seveal weeks -- when new leaves and stems grow.

If the plant receives enough sunlight the plant will form buds during this time. If there is not enough sunlight, the plant will remain in vegetative cycle.

A blooming period of several weeks when little or no vegetative growth occurs.

The length of time they will bloom is dependent upon the health of the plant and the environment they are in, the more sun and heat, the better. However, long days and short nights (July and August in Florida) limit a bougainvillea ability to bloom. "

I guess the big pot is probably the problem - I guess I'll yank it out and look at the roots and move it down if needed (I used the big pot because I wanted to use the iron trellis). It definitely gets plenty of light. Maybe some fertilizer, although I remember reading that they really prefer very little of it. Thanks!