Many thanks Peaspec.--certainly looks like that could be it--(do some campanulas not bloom as a bell shape?)-----and also, why some petals 5 and some 6?
Hi Kenny, not sure why there is a 6th petal on some and not others (generally campanulas have just x5)- possibly a mutation over time (?)
Yes, some plants of the campanula species have flatter flowers, which is odd as the meaning of the name is 'little bells', but they are about.
I'm no expert - my mind pinged straight to the 'Blue Waterfall' as I nearly bought one at the garden centre yesterday ;-)
All the best