Hi Luit,
thank you very much for the link - I've just had a quick peek. I certainly will print out some of the information for future reference as it looks like a very comprehensive and informative site.
As Darren said I have been on work experience at the nursery today. Very aptly todays job was to line out the bulbs ready for the nursery reopening on 01st Feb.
It was lovely to look at the sales tables full of pots, with their healthy little shoots and in a few cases flowers. I spent a lot of time potting up the bulbs in the autumn, so it was great to see them looking so well. I am looking forward to seeing them in flower - there are 26 different narcissus varieties alone, so it should be a colourful display.
Thanks again to everyone for their help.
Susan