No, that won't help :-) These are just getting hit very hard by the past couple of very cold winters. If you want earlier blooms you will need to provide winter protection.

Protect the crown area especially, with a mound of dense mulch. "Crown shock" (leaving too much crown exposed to winter) has happened randomly to all of my ES at some point, where they are slow to start.

one of them actually has buds on it now, so there is hope for this year. I will definitely mulch heavier this fall and see what happens. Thanks.