Hong Kong Orchid Tree - Bauhinia blakeana
Fast growth and spectacular blooms always attract attention but not suitable for high pH soils.
Crape Myrtle Tree - Lagerstroemia indica
Better inland than on the coast. It is hard to beat the Crape Myrtle for spectacular summer color in the hot inland areas.
Purple or Pink Trumpet Tree - Tabebuia impetiginosa
Slower growth than some trees but flower show is a traffic stopper.