How about....lack of warm sunshine.

I have Allium Globemaster and they are thriving so I am not too sure, which type of Allium are they?

Are you sure you did not miss the flowering and what you can now see are the seed heads on the dried up stems?

Owd, I thnk you could be right, I bought 2 purple sensation and have now realised that they have already flowered and that what I thought were buds are actually seed heads.

Thanks for all those replys. I think Owdboggy might be right as I have been on holiday for just over two weeks and might have missed them. What a great website this is. I only sighned up yesterday and had 4 replys in less than a day. Thanks