Being a Perennial Geranium lover as I am. I can highly recommend the "Johnson Blue". It has a lovely leaf, and it does bloom through out the summer.
As well, it is a very tough plant, which over winters, in the colder climates, without any problems.
These are very pretty and different from your average geranium. Although mine took almost two full seasons to flower, and they came up pink due to soil ph....I would still recommend this variety.