Overview
Saponaria officinalis 'Rubra Plena' is a perennial in the genus Saponaria, part of the Caryophyllaceae family. It typically grows around 1.0 m tall. Saponaria officinalis 'Rubra Plena' grows best in full sun, and tolerates most soils. Its UK hardiness is rated H7. It is native to Europe and Western Asia.
About the genus
Saponaria is a genus of flowering plants in the family Caryophyllaceae. It is usually characterized by pink or white flowers.
Wikipedia contributors, "Saponaria", CC BY-SA 4.0 — Saponaria
In the garden
Saponaria officinalis 'Rubra Plena' is a perennial soapwort from Europe and Western Asia, a member of the Caryophyllaceae. It grows to around 1.0 m and carries mildly fragrant flowers through the summer months, flowering from June to September. The cultivar offers sustained seasonal bloom without the need for specialist soils. Place it in full sun where soils remain moist but drain freely; it adapts to sandy, loamy or clay substrates. Being H7 (fully hardy), it withstands UK winter conditions and corresponds roughly to USDA zones 4–8. Give plants a consistent supply of moisture in warm weather to keep flowering steadily, but avoid waterlogging. Use Soapwort 'Rubra Plena' in sunny herbaceous borders, cottage-style beds or alongside paths where its mild scent can be appreciated on warm days. It fills a mid-border position at about 1.0 m tall and provides summer continuity when paired with other full-sun perennials. Expect the main ornamental interest to be its summer flowers and gentle fragrance from June to September.
Growing conditions
Best soil and position for Saponaria
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy, Clay
- Soil moisture
- Moist but well-drained
- Exposure
- Full sun
- UK hardiness
- H7
Plant details
Saponaria officinalis 'Rubra Plena' size, habit and characteristics
- Plant type
- Perennial
- Height
- 1.0 m
- Native to
- Europe, Western Asia
- Fragrance
- Mild
Care notes
Pruning and caring for Saponaria officinalis 'Rubra Plena'
- Propagation
- Division, seed
Frequently asked questions
Where is the best place to plant Saponaria officinalis 'Rubra Plena'?
Saponaria officinalis 'Rubra Plena' prefers full sun. It suits full sun positions.
What soil does Saponaria officinalis 'Rubra Plena' need?
Saponaria officinalis 'Rubra Plena' is adaptable and grows happily in most soil types, including sandy, loamy and clay. Aim for soil that stays moist but well-drained.
How big does Saponaria officinalis 'Rubra Plena' grow?
Saponaria officinalis 'Rubra Plena' reaches a height of 1.0 m.
Is Saponaria officinalis 'Rubra Plena' hardy in the UK?
Saponaria officinalis 'Rubra Plena' has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Saponaria officinalis 'Rubra Plena'?
Division, seed.
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