not that I am aware . I did something similar a few years ago and just had to take pot luck.

At the seedling stage, I've been told that the leaves on the white-flowered could be paler than on the purple-flowered.

Thanks Teadrinker - I will sow some, and then (perhaps) be able to give away the correct ones. In fact, some of the seeds seem to be paler than others, but maybe that's just chance.

Not just me then Eileen!