2 and a half times the depth of the bulb for how deep, about half inch apart, around 6/8 to a clump.

Hi, if you buy them from a garden centre in pots, they will have about this number in the pot, just plant to the same depth as the pot, within 2-3 years, the size of the clump will probably have tripled or quadrupled, but if you buy as loose corms, as above, Derek.

I was going to say don't worry! They grow very easily and will form a large clump very quickly as Derek says.

Thanks very much to all