I never really noted how long individual blooms last. But the spike will continue to grow and produce more flowers for few weeks up to one month. It has nice scent but very weak, you really have to stick your nose right up to the flower to detect it, and only in mid-morning.
The complete name on the tag is Dort. Pulche.(white/yellow splash) x Dort.Purche. var.Buyssonian (sp?) sorry the last few letters of the last name are not clear.

Thanks for the comments, makes me appreciate these tiny flowers more.

Tanya