This is an interesting hybrid from Dibley’s Nursery in Wales. Dibley’s has had a long-standing commitment to incorporating some of the more interesting and useful characteristics of previously under-used species in its hybridizing program. In this case, S. kentaniensis was used. This species has succulent narrow leaves and many small flowers. It is quite drought tolerant, and, most important, is not particularly day-length sensitive in its bloom cycle. This is particularly interesting from the point of view of growers in more northerly locales using natural light (on windowsills or in greenhouses), as most streps stop blooming during the very short northern winter.
In my case, well to the south of Wales, I have found ‘Crystal Ice’ to be a reliable bloomer, with many of its smallish white and blue flowers produced throughout the year. As with many British hybrids, best results are obtained when the plant is allowed to grow to a considerable size — the plant in the photo is in an 8″ pot. I think that this hybrid is particularly well-suited to windowsill culture — it seems to tolerate fairly low humidity in winter and thrives on the cool temperatures of a winter window. Its overall appearance can be so “perfect” that it has on several occasions been mistaken for an artificial plant!
I’ve also grown a plant of ‘Crystal Ice’ outside (in a pot on the edge of a veranda). It received direct late afternoon sun, and tolerated the heat of summer quite well, remaining in glorious bloom for months.
A slideshow of other views of this hybrid can be seen by clicking one of the links below.