@BrownJames. There are some with even better shades of blue that are much darker than this. I prefer them to be much darker blue ! There used to be a cultivar, spelled Ultraviolet', I think, which darkened as the bloom aged, but can't seem to locate it any more, for possible cross pollination.
I had grown it a couple of times, but unfortunately did not produce any seeds. They are actually rather easy to germinate, in warmth, as long as it isn't sown too deeply, or overwatered.