How to Grow Leatherleaf Fern
Rumohra adiantiformis
Leatherleaf fern produces thick, glossy, triangular fronds from creeping rhizomes and thrives in partial shade with consistently moist well-drained soil. More drought-tolerant than most ferns due to its water-storing rhizomes, but best growth comes from regular watering. Feed monthly in the growing season at half strength. Keep above 10°C. Prized in floristry for fronds that last 2-4 weeks in a vase.
Yearly Lifecycle
Care Essentials
Feed monthly with half-strength balanced fertiliser from spring to early autumn. Do not feed in winter when growth slows. Avoid over-feeding, which causes soft growth prone to damage.
Watch For
- Scale insects on frond undersides
- Mealybugs at frond bases near rhizomes
- Slugs and snails damaging young fronds
- Root rot from waterlogged soil
Care Requirements
Light
Partial shade; no direct sun.
Bright indirect light or dappled shade is ideal. Direct sun bleaches and scorches the leathery fronds. A north- or east-facing window works well indoors. Outdoors in mild climates, grow under tree canopy or in a sheltered shady border.
Watering
Keep soil consistently moist but well-drained.
Water when the top 2 cm of compost begins to dry. The thick rhizomes tolerate brief dry spells better than most ferns, but prolonged drought causes frond dieback. Never let the pot sit in standing water.
Fertilizing
Monthly half-strength balanced feed, spring to early autumn.
Apply a balanced liquid fertiliser at half the recommended strength once a month from March to September. Do not feed in winter. Over-feeding produces soft growth prone to pest damage.
Pruning
Remove old or damaged fronds at the base.
Cut spent fronds at the rhizome level with clean scissors or secateurs. New fronds unfurl from the rhizome tips continuously during the growing season. No other pruning is needed.
Humidity
Moderate to high humidity preferred — 40% or above.
More tolerant of average room humidity than Boston fern, but appreciates occasional misting or a pebble tray in heated rooms. Brown frond edges indicate humidity is too low.
Growing Tips
More forgiving than most ferns
Thick rhizomes store water, making leatherleaf fern more tolerant of occasional missed watering than delicate ferns like maidenhair. However, consistent moisture still produces the lushest growth.
Excellent cut foliage
Fronds last 2-4 weeks in a vase of water, making this one of the most popular greens in floristry. Cut fronds at the base when they are fully unfurled and mature.
Partial shade is ideal
Direct sun bleaches and scorches the leathery fronds. A bright spot out of direct sunlight, or dappled shade outdoors in mild climates, gives the best colour and growth.
Divide rhizomes in spring to propagate
Lift the plant in spring, separate sections of rhizome with at least 2-3 fronds attached, and pot individually into free-draining compost. Keep warm and moist until established.
Pests & Diseases
Pest Scale Insects
Identification: Brown or tan oval bumps on frond stems and undersides; sticky honeydew residue on nearby surfaces.
- Scrape off with a soft toothbrush dipped in soapy water; repeat weekly until clear.
- Apply neem oil solution to affected stems, avoiding new unfurling fronds.
- Systemic houseplant insecticide containing acetamiprid applied as a soil drench.
Pest Mealybugs
Identification: White cottony clusters at frond bases and where fronds meet the rhizome; fronds may yellow and wilt.
- Dab colonies with a cotton bud soaked in rubbing alcohol.
- Spray with dilute insecticidal soap solution, ensuring good coverage of frond undersides and rhizome crevices.
- Systemic insecticide drench containing imidacloprid for persistent infestations.
Disease Rhizome Rot Pythium spp. / Rhizoctonia solani
Symptoms: Fronds yellow and collapse; rhizomes become soft, dark, and foul-smelling rather than firm and tan-coloured.
Treatment: Remove plant from pot, cut away all soft rhizome tissue with a sterile blade, dust cut surfaces with sulphur powder, and repot into fresh free-draining compost. Water sparingly until new growth appears.
Prevention: Use a pot with drainage holes and a free-draining mix with perlite or bark. Never allow the plant to sit in standing water. Plant rhizomes shallowly, with the top surface exposed to air.
