splitting poppies?

Hi, Gaz, as you probably know perennial Poppies normally behave like other hard perennials in that they shoot out of the soil, produce foliage and flowers and then die back again. But differently they will sometimes reappear with foliage weeks after dying down and stay in foliage during the Winter as some of mine have done due to the mild Winter.
The best time to split them is after they have flowered and died down. If you leave just a scrap of root behind you'll have another, smaller, Poppy there again next year!!!

 

The problem with Perennial Poppies when you move them in leaf, Silu, is that that they don't take kindly to it. The plant just flops over onto the soil and looks like it's on it's last legs and might look like that for a week of two. You will probably get some leaves turning brown and dying off but I've never lost a plant so far whether split and moved into a new site or pot while watering them daily. The other thing they might do is to disappear under the ground and you might think you lost it until a couple of months later it slowly appears again

 

Hi Scrungee. Yep, you're right, they're quite deep rooted and to be honest I've never ever cleanly taken all parts of the root out despite digging down deeply and carefully in my soft sandy soil. That's probably why my stock of Perennial Poppies keeps going up!!

 

Wait until it has flowered and the leaves are dying back slightly, so you're looking at end of September/beginning of October...........not in a hurry are you???? But keep it watered after the move.