I learnt last year that Tumbling Ted is what I know as Bouncing Bet, and is actually Saponaria ocymoides - if that's what you're talking about, best time would be early autumn, but you can do it when its finished flowering this year IF you're prepared to keep it watered till it re establishes itself.

This would be best before it starts to sprout in early spring. However, until then you could try propagating it from softwood cuttings anytime now.

thanks a lot

I have this in my rockery and I just pull a bit off without flowers and put it in gritty soil and keep watered till it takes