Asplenium onopteris
Asplenium onopteris · Aspleniaceae
The gardener's calendar
Ideal time to plant asplenium onopteris: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Evergreen, dark green
- Plant type
- Fern
- Mature size
- 15 to 40 cm in height
- Growth
- Slow to moderate
- Hardiness
- Low hardy (0 to 5°C)
- Origin
- Mediterranean and Atlantic regions
- Soil type
- Well-drained, moist, rich in organic matter
Care
Watering
Keep the substrate constantly moist without becoming waterlogged. Water regularly, particularly during the growing season (spring-summer). Reduce slightly in winter while maintaining some moisture. Prefer soft or filtered water to avoid limescale deposits on the foliage.
Light exposure
Place the fern in partial shade or indirect light. It dreads direct sun which would scorch its delicate fronds. A bright location but without direct rays is ideal, particularly near a north or east-facing window.
Soil and substrate
Use a light and airy mixture composed of leaf mould, peat or coconut fibre, and perlite or fine bark. Drainage is crucial to prevent rhizome rot. A slightly acidic pH is preferred.
Fertilizing
Apply diluted, balanced fertilizer (or nitrogen-rich) every 4 to 6 weeks during the growing season (April to September). Reduce or stop feeding in autumn-winter. Avoid high doses which could burn the fine fronds.
Pruning and cleaning
Regularly remove dead or damaged fronds at the base. Gently clean the foliage with a damp cloth to remove dust and encourage respiration. No drastic pruning: the fern regenerates naturally.
Diseases and pests
Watch for mealybugs and spider mites, especially in dry air. Rhizome rot appears in case of excess moisture or poor drainage. Ventilate regularly and check soil moisture to prevent these issues.
Did you know?
Asplenium onopteris, called the 'Alternate-leaved Spleenwort' in English, was traditionally associated with medicinal virtues in Mediterranean herbal medicine. Its scientific name comes from the Greek 'asplēnon', literally meaning 'without spleen', as it was once believed that certain ferns of the Asplenium genus treated spleen ailments — a curious but persistent belief in Antiquity.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- Maidenhair spleenwortAsplenium trichomanes
- Hart's-tongue fernAsplenium scolopendrium
- Wall rueAsplenium ruta-muraria
- Black spleenwortAsplenium adiantum-nigrum
- Asplenium ceterachAsplenium ceterach
- Green spleenwortAsplenium viride
Tips generated and checked by Viridia — adapt them to your local climate.