Artemesia? If so Which one?

I have a round bed with these plants defining the six 'segments' (where I want to put roses).

They are getting a bit scruffy and I wasn't sure if I should leave them, prune them or what!

 

Hi Jesaya
Are you sure they are Artemesia?
They look as if they could be Sencio Cineraria Silver Dust.
They look good and add character.
If they are Cinerera you can cut them back they will reshoot and you decide on how big they get.

 

I'm not well up on these, but I agree.
I dont think its artemisia, think roders has nailed it.

 

Hi - you are right, they are Sencio... I hope they survive the winter as they make a lovely frame for the roses

Thanks roders and Pete