That's a great idea for tabletop Christmas tree. There are only certain kinds of greenery approved for use in Advent wreaths (seriously, the Episcopal Church regulates everything) and one of them is rosemary. So it already has a Christmas-y association.

I've read the squash blooms can be eaten raw in a salad, so that's probably what I'll do with them. Fried would be wonderful, until I got on the scale! :D