if you dead head you may get more flowers later in the year.

You could also collect some seeds - if it's Geranium bohemicum, it tends to be an annual, but seeds itself, but you could grow some yourself.

Wait a bit - as the flowers fade, those long growths they're on will drop and sprawl. Keep an eye on the plant - what you're looking for is signs of new leaves coming from the centre of the plant. As soon as you see those (should be quite a good sized area of new growth) cut back all the long growths you had previously, leaving just the new growth to take over - this will flower again.

thanks guys

I've had this in my garden for over 30yrs and I've never deadheaded it yet, but I'll certainly take note of what Bamboo says as I've never done that before either. I'll look forward to another flush of flowers this year.