Once you buy a few plants of different colours, they seem to take care of seeding themselves on their own, coming up with miraculous new variations!
One mauve parent plant next to the plant label, produced five seedling plants.
These mixed themselves up with the following:
Mauve and red
White
And Pulsatilla vulgaris (formerly Anemone pulsatilla) 'Papageno'. They produced the following offspring and many more.
Their seed heads were allowed to mature and blow away to where they wanted to grow. Sandy soil and fairly dry conditions, but with a full snow cover for at least a month or two may have helped. These plants are also known as Prairie Crocuses and grow wild in many areas. I hope this can be of some help.