They will wither back naturally. The seed heads can be pretty for a time, but they can be cut down if they begin to look battered.

mine are all but dry/dead now with new growth just forming at the base. I will cut alll the dead stems out as soon as I can get in and sort it. I have left this until the spring before too, but they did look a mess.

I cut mine hard back as soon as they've finished flowering, so I can fill the gaps with something else. The new fresh leaves appear quite fast. I know it's a bit late telling you that - but you might like to think about doing it that way next year - they do look messy otherwise.

Ok thanks guys..yes mine do look a mess ..secateurs at the ready!! lol .. what sort of things could I plant around them then ..could I plant spring bulbs?

I don't think I would. You have to leave the foliage on the bulbs, and not take it off until about July.

Try something like Doronicum that flowers in spring, or possibly Salvia nemorosa to take over when the poppy finishes.

THANKYOU :))