Your blooms have less red than most H. Siren I've seen. Pretty though. Wonder if this is one of those blooms that vary from year-to-year.
K

This post was edited by kaboehm on Wed, Jan 1, 14 at 15:15

I looked it up to confirm that my Siren was not mis-labeled and the website shows three different pics. of Siren and they are all different. Mine looks more like the center pic. It must vary as you suspected.

http://www.easytogrowbulbs.com/p-28-amaryllis-siren.aspx

Here is a link that might be useful: siren pic easy to grow bulbs