Yes you can, wait until they finish flowering, lift them, and you will see several "crowns" get your fingers into the rootball, and just pull these "crowns " apart, replant the new plants in an out of the way spot, not in full sun, and grow them on until the end of september, then plant them out where you want them to flower, Derek.

I do it all the time....I have loads all over the garden.

And me, they have now taken to seeding themselves in the lawn and look really pretty, its fascinating to see how far the seed travels

Thanks to everyone who took the trouble to send me a reply, if it ever gets warm enough outside i will do that.
Thanks again.
Michael.