Sea Holly (Big Blue)

[Londondreamer]

Hi, I brought a Sea Holly, Big Blue earlier this year, it's in a container and seemed happy and flowered well,
Now it has stopped flowering and the seed heads have turned brown, which i assume it is supposed to do after the flowering season.

I don't know what to do with it now, does it need pruning later the year/ early spring, removing spent flowers and stems or do I need to cut it right down to the ground. I've tried googling and keep getting conflicting advice.

It was so lovely this year, I don't want to do it wrong and stop it coming back.

Any advice would be great.

The seed heads stand well over the winter and provide forage for birds and habitat for insects. Other than tidying up any tatty leaves and fallen flower stems I'd leave it be, other than keeping up with feeding and watering.

I'll definitely leave it through the winter, I just wasn't sure if it will flower next year with the old stems and flower heads still there.

Thanks for responding.