I don't grow a lot but they are certainly flowering well this year Cestrum Newellii by charliepridham, on Flickr
This one lives outside on a shaded west wall
In my (very limited) experience I have only seen the flower on second season wood.
I have tried some and fallen out of love with them quite quickly C parqui because although hardy I found it also boring, C nocturmum was hard work and only scented at night, I quite like the C Newellii above, both the foliage and flowers are OK, mine flowers 2 sometimes 3 times per year but I can never decide whether it is one long flowering interrupted by cold or 3 waves of flowers? I also have one called 'Cretan Purple' (you are welcome to one if passing), it is just finishing flowering but would need careful placing as its a somber colour