Pest identification
What's eating my hawaiian tree fern?
Scale insects
Signs: Hard or soft shells clustered on trunk fibre, stipes, and frond undersides; honeydew and sooty mold
Control: Scrub trunk and stipes with a soft brush and insecticidal soap solution; apply horticultural oil, repeating monthly
Mealybugs
Signs: White woolly masses embedded in trunk fibre and at frond bases; fronds yellow and wilt
Control: Remove colonies with forceful water jets and follow up with neem oil spray; repeat every 7–10 days
Spider mites
Signs: Pale bronzing and fine webbing on frond undersides; fronds dry out prematurely
Control: Raise humidity, shower fronds thoroughly, and treat with insecticidal soap or neem oil weekly for a month
Caterpillars (outdoor)
Signs: Irregular holes or ragged edges chewed from young fronds and croziers
Control: Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to new fronds for biological control
Keep hawaiian tree fern pest-free
Healthy plants resist pests best. Get the basics right:
Hawaiian Tree Fern pests — FAQ
What is eating my hawaiian tree fern?
Hawaiian Tree Fern (Cibotium glaucum) grown as a tropical specimen is most troubled by scale insects on its trunk and fronds. Mealybugs shelter in the soft fibre of the trunk base. Spider mites attack fronds in dry conditions. When grown outdoors in warm climates, caterpillars may occasionally chew young fronds.
How do I get rid of scale insects on hawaiian tree fern?
Hard or soft shells clustered on trunk fibre, stipes, and frond undersides; honeydew and sooty mold Scrub trunk and stipes with a soft brush and insecticidal soap solution; apply horticultural oil, repeating monthly
How do I get rid of mealybugs on hawaiian tree fern?
White woolly masses embedded in trunk fibre and at frond bases; fronds yellow and wilt Remove colonies with forceful water jets and follow up with neem oil spray; repeat every 7–10 days
How do I get rid of spider mites on hawaiian tree fern?
Pale bronzing and fine webbing on frond undersides; fronds dry out prematurely Raise humidity, shower fronds thoroughly, and treat with insecticidal soap or neem oil weekly for a month
How do I get rid of caterpillars (outdoor) on hawaiian tree fern?
Irregular holes or ragged edges chewed from young fronds and croziers Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to new fronds for biological control