It's a varigated Iris of some description....lovely plant though

Iris laevigata Variegata would be my guess.

(Japanese iris)

Never seen leaves like that on an iris, very attractive.

Lovely paired with the hosta in the background.

Many thanks for your replies. We have a house in Florida and seen it lots there so I was very excited to see it on a golf course near me. I love the foliage and the iris is gorgeous. Just need to find where I can buy one.

I wouldn't know, but it's so pretty :-)

Pdb, the RHS is showing 23 suppliers so it's probably fairly freely available - looks like something that you're likely to be able to get at your local water gardens store (try world of water if you're anywhere near Blackpool - or fancy a day out at the seaside!)
I have seen variegated irises at my local store - I chose variegated sweet flag (Acorus gramineus) and clematis-flowered iris (Iris ensata) instead, but may reconsider getting one of these next time round as they seem to be more bog plant than pond plant.