Isn't that the 'Andy Murray' hosta Kim is holding?
Well you would surely think so, Iona. A fantastic photo opportunity.
But in this article it says it is so named because of its "blue and white leaves which are reminiscent of the Scottish Saltire." http://www.yourashford.co.uk/news/chelsea_flower_show_to_serve_up_andy_murray_flower_1_3600913
Doesn't much look like that to me, so maybe she's just been given a random hosta to hold!
But what do I know? - maybe the colour alters in the winter months.
Over to the gardeners amongst us!