S. johannis is a species that has been much used in the production of floriferous and vigorous hybrids, including the classic ‘Constant Nymph’. The specimen illustrated above, while obviously vigorous and healthy, is not demonstrating the floriferous quality for which the species is known.
In nature, the species is most often seen in its pale blue form, examples of which can be viewed by clicking here, here, and here. This is an interesting variant of the species with somewhat exaggerated lobes. This is an unusually large-flowered form. The flowers in this photo are the correct colour — in the other photos, the colour is much warmer, more purplish, which is a function of the film — this photo was taken with a digital camera. Another form with somewhat wider and differently shaped flowers has been grown by Prof. Bellstedt. This form has significantly wider flowers than the more widely distributed forms, as does this one. It is possible that close study would reveal that the species could be divided into two or more species.