Expert: C.L. Fornari - 12/4/2006

Question
I forgot to ask, what time of year is the best time to cut it back?  I live in San Jose CA where the weather is not as harsh as other areas of the country.  If a Dec trim is ok should I cover the plant on those frosty nights?
Thanks again.  Jim
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
It is Dec 2nd and I was trimming up my frost burned Bogenvia.  My neightbor suggested I hack my 12'(H) x 5'(w)x 4'(d) down to 3' high.  Before I kill this beautiful plant which climbs my chimney, what is the proper care of my Bogenvia?  PS I have only trimmed this plant for the last 7 years.  Thanks, Jim
-----Answer-----
Jim,
I'm not sure why your neighbor would want you to drastically prune your Bougainvillea... you can cut it down so low if you need to reduce it's size, or if it had a great deal of frost burn, but otherwise there is no need to.  If the plant gets too large the best thing to do is to cut it back by a third, or, if possible, to cut some of the vines back by 2/3 and some by 1/3...this is often difficult as they get all twined together, so most cut the entire thing back when it gets too large.  As long as your plant is still OK on your chimney, continue to do what you've been doing.  Perhaps your neighbor is an ex-Marine Corps Barber... :-)
all the best,
C.L.

Answer
Jim
Bougainvillea go through a growth period, followed by a blooming period, followed by a rest period, so although you can prune it any time, it's really best to do a hard pruning (to control size) right after it blooms.  When conditions are right it sets flower buds after the growth period, so if you prune it at that time you'll be cutting flowers off.

If it has finished blooming for this season go ahead and cut it back.

Also, when it starts the growth period and gets long straight stems growing, you can get them to bush out by pinching the tip off of those long canes.

Do protect this plant from frost - it is a tropical plant and can be killed by a few hours of sub-freezing temperatures.

all the best,
C.L.