Sempervivum 'Onyx' (SuperSemps Series)
A mat-forming, evergreen alpine succulent to around 20cm in height, with rosettes of large, dark purple to mahogany black leaves. Starry pink flowers on slender stalks appear above the foliage from June to August
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Black Brown Purple | |||
|---|---|---|---|---|
| Summer | Pink | Black Brown Purple | ||
| Autumn | Black Brown Purple | |||
| Winter | Black Brown Purple |
Position
- Full sun
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H5Botanical details
- Family
- Crassulaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- Habit
- Matforming
- Genus
Sempervivum are evergreen perennials forming mats of fleshy-leaved rosettes, often attractively coloured, with star-shaped pink or pale yellow flowers in summer
- Name status
Accepted
How to grow
Cultivation
Grow in moderately fertile, well-drained soil in full sun. Protect from excessive winter wet. Suitable for rock gardens, scree beds, wall crevices, troughs or alpine houses. See cacti and succulent cultivation for further advice
Propagation
Propagate by offsets in spring
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Gravel garden
- Houseplants
- Patio and container plants
- Rock garden
- Conservatory and greenhouse
Pruning
No pruning required
Pests
May be susceptible to sempervivum leaf miner, slugs, snails, and vine weevil
Diseases
May be susceptible to a rust
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