Sorry it's taken me a while to respond to all your comments - they are much appreciated!
I was quite taken by Footle's description: 'It's a squiggly thing.' 
Having googled your various suggestions, I do think it is indeed Anthemis punctata and it does seem to sprawl so I imagine it is subspecies cupaniana. The foliage is very soft. I can't tell whether it has a particular smell - my nose isn't very sensitive.
It's hard to find close-up pictures of foliage on Google. On photos of plants, the flowers always seem to cover up the leaves or the leaves are out of focus because the flower is considered more important (makes the photo 'pretty').
Anyway, it seems to be doing well so I look forward to seeing the flowers next year!