If it is the same butterfly bush as I have - Buddleia davidii, - long greyish -green leaves & drooping plumes of tiny flowers? Yes, it is a lovely thing & the butterflies really do like it. Quite an 'informal' growth habit so needs plenty of room. Likes sun & well drained soil. Cut it back hard to the ground each spring & feed it . It will send up fresh growth & dozens of blooms. Enjoy.
My Aunt has one that is more like a tree! It was supposed to be a bush, but it is quite the big thing so I am wondering if it was labeled incorrectly at the store?
It is quite pretty and she gets a lot of butterflies each year too, so yes they do work. She gets different kinds of butterflies, but more Monarchs then others since that is what we have a lot of around here.
I'm sure that it will produce beautiful flowers, you just have to be patient. I agree, the Twilight one looks very pretty, although I must say that I prefer more delicate colors...I'm in a romantic mood