Mediterranean Spleenwort Plant Care
Asplenium onopteris L.
Updated · Sources · How we source care data
Asplenium onopteris, known as the Irish spleenwort or western black spleenwort, is a species of fern mostly found throughout the Mediterranean Basin but also around the Eastern Atlantic.
Every 7–10 days
Bright indirect light
60–75°F
50–70%
At a glance
How do you care for Mediterranean Spleenwort?
Water Mediterranean Spleenwort every 7–10 days, letting the top layer of soil dry out between waterings, and give it bright indirect light. It prefers temperatures of 60–75°F (16–24°C) and 50–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Mediterranean Spleenwort?
Mediterranean Spleenwort (Asplenium onopteris) belongs to the Aspleniaceae family within the Asplenium genus.
Mediterranean Spleenwort displays a compact, clumping fern growth habit, reaching up to 1.5 ft tall with a spread of approximately 1.5 ft. Mediterranean Spleenwort produces non-flowering plant.
Leaf size: approximately 12 inches.
How Often Should You Water a Mediterranean Spleenwort?
Asplenium onopteris requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Mediterranean Spleenwort Need?
Mediterranean Spleenwort thrives in bright indirect light. Avoid placing Mediterranean Spleenwort in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect light
What Temperature and Humidity Does the Mediterranean Spleenwort Prefer?
Asplenium onopteris grows best at temperatures of 60–75°F. Mediterranean Spleenwort prefers humidity levels of 50–70%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
60–75°F
Humidity
50–70%
What Soil Mix Works Best for a Mediterranean Spleenwort?
Moist, well-draining soil with high organic matter content. Good drainage is essential for Mediterranean Spleenwort to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Mediterranean Spleenwort?
Feed Mediterranean Spleenwort every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Mediterranean Spleenwort?
Repot every 1-2 years in spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Mediterranean Spleenwort?
Mediterranean Spleenwort can be propagated through spores, division of rhizomes. Similar propagation techniques also apply to birds nest fern plant care, which shares the same genus.
Is the Mediterranean Spleenwort Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Mediterranean Spleenwort, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Mediterranean Spleenwort?
Mediterranean Spleenwort is susceptible to spider mites, mealybugs, scale insects. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Mediterranean Spleenwort Need?
Mediterranean Spleenwort grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. In cooler regions, grow Mediterranean Spleenwort as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Mediterranean Spleenwort is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Asplenium genus — compare its care with other Asplenium species on PlantoScan.
Asplenium is part of the Aspleniaceae plant family — browse all Aspleniaceae genera and species.
Mediterranean Spleenwort thrives in bright light and direct sun — see other bright-light plants.
More Asplenium Species
Other Asplenium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Asplenium onopteris L., family Aspleniaceae (first published in Sp. Pl. : 1081 (1753)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Mediterranean Spleenwort, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 13a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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