I posted this same Allium on 9th of July when it was in an earlier stage of development; I left it in water in the conservatory and, like it's brothers and sisters in the garden, it's continued to flourish.
The previous shot is here The bees and butterflys are loving it, the bed that they are in, in the front garden, is awash with pollenators.
This is known as an 'Onion Allium' or 'Bristol Allium' or 'Round Headed Leek' - the only place it grows wild in the UK is in the Avon Gorge near Bristol in the South West of England.