The so called
Bonsai Form may flower smaller.
Note that it has a yellow throat to the bloom, and appears to have the whole panicle open at once.
I think it is a hybrid, Radermachera currently has
17 species.
There is a good chance the Bonsai Form has flowers that last beyond morning coffee.
It is a spectacular foliage plant in the tunnel, the flowers were unexpected and impressed John enough to get him over here as a 'special' trip all the way from the other side of the hill.
Chad