Overview
Petrophytum caespitosum is a plant with a mat-forming habit in the genus Petrophytum, part of the Rosaceae family, with evergreen foliage. Petrophytum caespitosum grows best in full sun, and tolerates loam soils and neutral pH. Its UK hardiness is rated H4. Suggested uses include alpine garden, rock garden and trough planting.
About
Petrophytum caespitosum, commonly known as mat rock spiraea, is a mat-forming evergreen plant from the Rosaceae family. It thrives in full sun on a south-facing, sheltered aspect and prefers well-drained, neutral loam soil. Hardy to UK zone H4, it is suitable for alpine gardens, rock gardens, and trough planting. This cultivar is of particular interest in spring and summer. It requires watering during establishment and can be propagated by seed or division.
About the genus
Petrophytum is a small genus of plants in the rose family known as the rock spiraeas or rockmats. These are low mat-forming shrubs which send up erect stems bearing spike inflorescences of flowers. The brushy flowers are white and have many stamens and hairy, thready pistils.
Wikipedia contributors, "Petrophytum", CC BY-SA 4.0 — Petrophytum
Growing conditions
Best soil and position for Petrophytum
- Sunlight
- Full sun
- Soil type
- Loam
- Soil pH
- Neutral
- Soil moisture
- Well-drained
- Aspect
- South-facing
- Exposure
- Sheltered
- UK hardiness
- H4
Plant details
Petrophytum caespitosum size, habit and characteristics
- Habit
- Mat-forming
- Foliage
- Evergreen
- Suggested uses
- Alpine garden, rock garden, trough planting
Care notes
Pruning and caring for Petrophytum caespitosum
- Propagation
- Seed, division
- Pest resistance
- Generally pest-free
- Disease resistance
- Generally disease-free
Frequently asked questions
Where is the best place to plant Petrophytum caespitosum?
Petrophytum caespitosum prefers full sun. It suits sheltered positions.
What soil does Petrophytum caespitosum need?
Petrophytum caespitosum grows best in loam soil. It prefers neutral soil. Aim for soil that stays well-drained.
Is Petrophytum caespitosum hardy in the UK?
Petrophytum caespitosum has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.
How do I propagate Petrophytum caespitosum?
Seed, division.
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