Aquilegia .....or as we call them hete in the UK 'granny bonnets' Beautiful, easy to grow and truly delightful.

Definitely an Aquilegia which come in a huge variety of colours and doubles, single, bi-colours etc. They don't grow true from seed, so it's always an exciting time to see what you have got!
Have a look at the following site for a mouth-watering selection. http://www.touchwoodplants.co.uk/aquilegias.htm

Thanks to you both. I didn't realise when I originally posted that I actually have some Aquilegia in the garden already i.e. the pink ones in the 2nd pic I've added. They're nice but nowhere as nice as the violet and white ones, I'd love to get my hands on some of those, I'll check out the link you've kindly provided and see if I can buy some.

Have a look for a packet of McKana hybrid seeds. they are fairly easy to grow and you do get a selection of larger flowered, mixed coloured plants.

Many thanks, will do. I suppose it's too late to grow any for this year?

Sown now, they would flower next year.

Thanks, I must buy some now then.
P.S. Is McKana hybrid the same as Aquilegia Caerulea
http://en.wikipedia.org/wiki/Aquilegia_caerulea
If you look at the pic of the Colorado Blue Columbine at the top of the link, they look identical?

Not really. The Mckana hybrids are a mix of lots of different species.