Garden

We headed off to Screwfix this morning to buy a power washer. 
I assembled it and spent the whole afternoon blasting the composite deck. Not sure what my back is going to make of it tomorrow.. Anyway the decking is much improved. As the evening approaches it's noticeable how colours become more vibrant. I've done very little in the garden this year due to the weather and as I looked around for a blip I realised some of the plants were flowering and I'd barely noticed.
I know the clematis, rock rose and potentilla but no idea what the blue flower is.. It is in a pot neglected under the bird bath, whatever it is, it's a beauty..