I don't know what you mean by 'normal' Euphorbia - certainly the woodland spurge pops up on its own and spreads everywhere. Ascot Rainbow is a sport of E. martinii -I'd guess if that were invasive, this one might be too, but I have 4 different Euphorbias in my garden and none of them is invasive. Best planted in spring, by the way.

Cheers Bamboo, I like the look of this but wont bother if it spreads like wildfire!

There are a few invasive Euphorbia's, such as E.robbiae and worst of all any variety of E.cyparissias, such as 'Fen's Ruby'. 'Ascot Rainbow', a super new variety of martinii, will not be in the least invasive-you will be quite safe with it!

Thanks Keitha, I think i will buy a couple of them!

It was putting me off a bit, Only just cleared the garden from the last Euphorbia's the previous owner planted they were popping up everywhere.