Overview
Ceterach officinarum is a fern in the genus Ceterach, part of the Aspleniaceae family. Ceterach officinarum grows best in partial shade, and tolerates most soils and alkaline pH. Its UK hardiness is rated H7. Suggested uses include rock gardens, walls and crevices. It is native to Flanders.
About the genus
Asplenium is a genus of about 700 species of ferns, often treated as the only genus in the family Aspleniaceae, though other authors consider Hymenasplenium separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is Asplenium marinum.
In the garden
Ceterach officinarum is a fern of the spleenwort family (Aspleniaceae) native to Flanders and established in rocky, lime-rich habitats. Its ecological niche is on exposed masonry and limestone outcrops, which matches garden situations where drainage is excellent and soil is alkaline. Plants perform best where they can find narrow pockets of mineral substrate rather than deep, moisture-retentive soil. Plant into joints, rock crevices or the gravelly pockets of a rock garden and place where it receives partial shade, especially on north or east-facing aspects. A sheltered position will reduce dessicating winds; avoid exposed sites where moist soils can develop. Use a free-draining, calcareous growing medium and keep soil moisture on the dry to moderate side once established — this species does not suit heavy, waterlogged ground. In the UK it carries an H7 rating, so frost is not usually a problem provided drainage and aspect are correct. Recommended garden uses are walls, rock gardens and crevices where alkaline mortar or limestone provides the substrate it needs. For best results tuck plants into mortar gaps or stony pockets on older limestone walls so they root into the mineral substrate they prefer.
Growing conditions
Best soil and position for Ceterach
- Sunlight
- Partial shade
- Soil type
- Well-drained, rocky, calcareous
- Soil pH
- Alkaline
- Soil moisture
- Dry to moderate
- Aspect
- North, East
- Exposure
- Sheltered
- UK hardiness
- H7
Plant details
Ceterach officinarum size, habit and characteristics
- Plant type
- Fern
- Suggested uses
- Rock gardens, walls, crevices
- Native to
- Flanders
Care notes
Pruning and caring for Ceterach officinarum
- Cultivation
- Prefers dry, well-drained soil; avoid waterlogging
- Pruning
- Remove old fronds in spring
- Propagation
- Spores, division
Frequently asked questions
How do I grow Ceterach officinarum?
Prefers dry, well-drained soil; avoid waterlogging.
Where is the best place to plant Ceterach officinarum?
Ceterach officinarum prefers partial shade. It suits sheltered positions.
What soil does Ceterach officinarum need?
Ceterach officinarum is adaptable and grows happily in most soil types, including well-drained, rocky and calcareous. It prefers alkaline soil. Aim for soil that stays dry to moderate.
How do I prune Ceterach officinarum?
Remove old fronds in spring.
Is Ceterach officinarum hardy in the UK?
Ceterach officinarum has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Ceterach officinarum?
Spores, division.
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