Chiastophyllum oppositifolium

About this cultivar:

Chiastophyllum oppositifolium, or whatever you want to call it,  has gained the Royal Horticultural Society's Award of Garden Merit - and rightly so. It is a succulent, perennial flowering plant. It is a hardy, prostrate evergreen growing to about one foot with large fleshy leaves and racemes of tiny, sulphur-yellow flowers. Great in a rock-garden it is unfairly seen as a rock-garden-only plant or a shade-only plant. We grow ours in a few pots, at the edge of well drained borders, beside a path and over a wall. It is tough! Just make sure it is not water-logged.

• Position: Full sun, partial shade
• Soil: Almost any soil, grows well in Ballyrobert
• Flowers: June, July, August
• Other features: Grows well in Ballyrobert, Royal Horticultural Society Award of Garden Merit (RHS AGM), Suitable for Container
• Hardiness: Fully hardy - grows well in Ballyrobert!
• Habit: Mat forming
• Foliage: Evergreen
• Height: 15 - 30 cm (2 - 3 ft)
• Spread: 30 - 60 cm (1 - 2 ft)
• Time to full growth: 2 to 5 years
• Plant type: Herbaceous Perennial, Alpine or Rockery
• Colour: Yellow, green
• Goes well with: A wall, a path, front of a border
  

About this genus:

Chiastophyllum actually doesn't seem to exist as a genus anymore. In fact there only ever appears to have been one species within the genus- Chiastophyllum oppositifolium - which is now know as Umbilicus oppositifolius.

So what about the genus Umbilicus? Well it is a genus of over ninety species of flowering plants in the stonecrop family( Crassulaceae). Many of its species have been given synonyms under different genera such as Rosularia, Cotyledon, and Chiastophyllum. 

That is all I'm going to say before I get taken to task by y any member of the latin/ greek/ botanical/ horticultural/ taxonomist police........