In article ,
says...

My Tibouchina semidecandra had been a lot happier this summer than
most, and has really come into its own as the chill has started.
While it is tender, I get the impression that it doesn't like
temperatures of above 15 Celsius. It certainly likes mist, and
gets unhappy in dry conditions.

Will it grow outside (clearly not here), and would keeping it in
a large pot of free-draining J.I. compost help? It is certainly
happy with my mixture.

And, of course, it is spectacular and flowers for ages. But you
knew that!


Regards,
Nick Maclaren.

I suspect that your plant is T. urvilleana, and the good news is that
this comes from the base if destroyed by frost, however before getting
carried away and leaving it out the plants in my open garden beds are
still only a foot high after last years winter, the late frost making
them even shorter than normal. I don't actually expect them to flower and
they are only the byproduct of planting out large plants from pots, my
main display comes from 2 year old pot fulls.
You are correct about the high temperatures, the colours on out door
plants are much more vivid and they grow better out, even the leaves
look better grown cold.
They are frustrating close to being growable so I keep trying! my present
attempt is at the base of a west wall, and I am also trying Tibouchina
grandifolia (which may turn out to be T. heteramala) so far I have not
got even the roots to survive, while T paratropica would probably be
hardy for you too as it behaves as a perennial, unfortunately the flowers
are smaller and white so not the same impact!
--
Charlie Pridham, Gardening in Cornwall
www.roselandhouse.co.uk
Holders of national collections of Clematis viticella cultivars and
Lapageria rosea