Plant
- Semitropical, grown as foliage houseplant
- Woody shrub where hardy
Stem
- Opposite leaf arrangement
- Succulent or woody on older stems
Leaf
- Thick, succulent
- Opposite, simple, smooth-edged
- Lacking petioles
- Green, sometimes with red edge or white variegation
Flower
- Small, in clusters on mature plants
- 5-petaled, star-shaped
- White, faint pink