Photo: Jacqui GeuxCC BY 4.0via iNaturalistresized / cropped
Black Stem Maidenhair Fern Plant Care
Adiantum formosum R.Br.
Updated · Sources · How we source care data
This delicate fern is easily recognized by its dark, wiry stems and elegant, fan-shaped fronds. Originating from New Zealand, Adiantum formosum's graceful appearance and ability to thrive in low light settings make it a coveted addition to any plant collector's collection.
Every 3–7 days
Bright indirect light
60–75°F
50–80%
At a glance
How do you care for Black Stem Maidenhair Fern?
Water Black Stem Maidenhair Fern every 3–7 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 50–80% humidity. Fertilize it every 6 months during the growing season.
Where Is the Black Stem Maidenhair Fern Native To?
What Is the Black Stem Maidenhair Fern?
Black Stem Maidenhair Fern (Adiantum formosum) belongs to the Pteridaceae family within the Adiantum genus. Black Stem Maidenhair Fern is native to Australia and New Zealand.
Black Stem Maidenhair Fern displays a fern with delicate fronds growth habit, reaching up to 1.5 ft tall with a spread of approximately 1.5 ft. Black Stem Maidenhair Fern produces non-flowering plant.
Leaf size: approximately 12 inches.
How Often Should You Water a Black Stem Maidenhair Fern?
Adiantum formosum requires watering every 3–7 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 3–7 days
Let soil partially dry between waterings
What Light Does the Black Stem Maidenhair Fern Need?
Black Stem Maidenhair Fern thrives in bright indirect light. Avoid placing Black Stem Maidenhair Fern in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Bright indirect light
What Temperature and Humidity Does the Black Stem Maidenhair Fern Prefer?
Adiantum formosum grows best at temperatures of 60–75°F. Black Stem Maidenhair Fern prefers humidity levels of 50–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.
Temperature
60–75°F
Humidity
50–80%
What Soil Mix Works Best for a Black Stem Maidenhair Fern?
Rich, well-draining soil with high organic matter content. Good drainage is essential for Black Stem Maidenhair Fern to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Black Stem Maidenhair Fern?
Feed Black Stem Maidenhair Fern 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 Black Stem Maidenhair Fern?
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 Black Stem Maidenhair Fern?
Black Stem Maidenhair Fern can be propagated through spores, division of rhizomes. Similar propagation techniques also apply to adiantum bellum plant care, which shares the same genus.
Is the Black Stem Maidenhair Fern Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Black Stem Maidenhair Fern, 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 Black Stem Maidenhair Fern?
Black Stem Maidenhair Fern is susceptible to aphids, scale insects, spider mites. 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 Black Stem Maidenhair Fern Need?
Black Stem Maidenhair Fern grows outdoors in USDA Zone 13a – 11b. It survives winters down to planting zone 13a. Black Stem Maidenhair Fern is native to Australia and New Zealand. In cooler regions, grow Black Stem Maidenhair Fern as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a – 11b
Keep exploring plants
Black Stem Maidenhair Fern 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 Adiantum genus — compare its care with other Adiantum species on PlantoScan.
Adiantum is part of the Pteridaceae plant family — browse all Pteridaceae genera and species.
Black Stem Maidenhair Fern thrives in bright light and direct sun — see other bright-light plants.
More Adiantum Species
Other Adiantum species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Adiantum formosum R.Br., family Pteridaceae (first published in Prodr. Fl. Nov. Holland. 155. 1810. HB. 119. Chr. 137. (1810)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Black Stem Maidenhair Fern, 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.
- Photo: Jacqui Geux, CC BY 4.0, iNaturalist — original.
- Hardiness zone: USDA Zone 13a – 11b, 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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