There is a Netherlands website on these plants, although I have seen additional varieties to those on this current "assortment", unless they pick up additional names depending on the local royal family names. Note the plantbreeder rights. http://www.princesslilies.nl/Engels/Default.htm I have mixed results with these in pots, due to erratic feeding and watering I suspect. A commercial grower of the larger cut flower types told me it is all in the feeding, as soon as the leaves show any sign of yellowing they need a feed. The leaves should be a healthy dark green all the time for good flowering. If only the dwarf types were so accommodating. Brian Whyer, zone 8'ish, Buckinghamshire, UK