Question
I live in San Diego, CA. I bought a house that has a neglected bouganvilla tree that has grown to about 7 feet tall with thorny stocks growing out of the top for several feet.  In order to more easily trim the tree I am wanting to cut it dowm to a more managable size but the main trunk is very undefined and has several smaller stalks growing out of the ground as well.  How do I trim this tree down to size and still have it bloom later on?
Thank you.

Answer
Hi Brian,
Thanx you for your question.  Bougainvillea is actually a woody vine and not a tree.  Here is a link I think you will find useful.

http://www.bgi-usa.com/bougainvillea-resource/bougainvillea-101.php#pruning_and_...

What you're talking about is a hard prune.  You can hard prune your bougainvillea down almost to teh ground if you like.  It will sprout new growth.  I think what you are wanting to do is cut the majority of the plant down.  Choose the main leader and then select the side leader you want to keep.  I would cut it all down to about 2 feet.  It will bloom later after it begin sending out new growth.  The link  I show you above tell the flowering cycle of the plant.  Keep trimming it all year to keep it under control.  Be careful of the thorns.  If you do not anticipate a hard frost any time before January.  It is safe to hard prune now, otherwise, I would wait until after the last frost period in your area, if you have one.  I hope this helps and let me know if you need anything else.
thx,
Tom