Same thing has happened to ours in France
It's not very mature , and all the growth has died off at about1"- looks like they would have been the flowers.
However there are a few new stems with leaves on growing now.
As far as I am aware there were no frosts, but that part of the garden is in a bit of a wind tunnel ( the young bay tree nearby has most of it's leaves browned off)

Do you think it may have been due to a chilled wind???


Oh- and welcome to the Vine!!