Vinca major

Mine is white. Very pretty flowers but the plant itself is incredibly invasive, that's the only problem...

Pretty - and I like the face that it spreads.

It is very invasive here too Tommymoo. I have it everywhere where it is not a problem. I have some vinca minor which is white (very invasive as well). I was surprised to find a white ones among blues this year. Just a few.
Do you grow it Sheila?

"face" above should read "fact" - sorry. Yes, I do grow it, Klahanie . . . mine is quite a deep blue with variegated foliage, brightening up some dappled shade.