The message
from "Anthony Stokes" contains these words:

My Albizia is still small (I grew it from seed) after 15 years it has just
reach 12" it is very late into growth and puts on some extension most of
which is lost in winter.
Leaves are pretty though and it seems hardy enough just slow, so buying an
imported large one may be the way to go.

I think that's 12 feet not 12 inches you mean, as my greenhouse albizia has
grown more than 12" ( inches) since June this year.

The only flowering one I've seen is in the walled garden of the RHS at
Wisley.
It had an abundance of pink scented flowers during August last year.
So far as I can see it lives in the same spot of the walled garden all year
round and doesn't suffer badly from branches dying off in the winter.

My seven foot high out-of-doors specimen seems very prone to the higher
leaves turning yellow and falling off in mid summer; although the soil is
generally kept moist.
Maybe some trace nutrient is in short supply.

Mine lives in a pot in the greenhouse in winter and comes out for the
summer. It has flowered for the last two years. It does tend to lose its
lower leaves so has become a little leggy but I put that down to less
than perfect care.
I simply added Osmocote to the compost when I potted it and try to stop
it drying out too much. It's about five feet tall..
Janet G