Pest identification
What's eating my zamia fern?
Scale insects
Signs: Brown or tan waxy bumps on fronds and stems; yellowing foliage and sticky honeydew residue
Control: Scrape off manually, apply isopropyl alcohol with a cotton swab, or treat with horticultural oil spray; repeat every 2 weeks
Mealybugs
Signs: White cottony clusters in leaf axils and along the rachis; stunted new growth
Control: Dab with 70% isopropyl alcohol, spray neem oil solution, or use insecticidal soap; isolate the plant immediately
Cycad blue butterfly (Theclinesthes onycha) caterpillars
Signs: Chewed and skeletonized emerging fronds on outdoor specimens
Control: Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to new flush growth in spring and summer
Keep zamia fern pest-free
Healthy plants resist pests best. Get the basics right:
Zamia Fern pests — FAQ
What is eating my zamia fern?
Zamia Fern (Bowenia serrulata) is troubled mainly by scale insects and mealybugs when grown indoors, and by cycad blue butterfly caterpillars outdoors in its native Queensland habitat. Spider mites can also attack plants kept in dry indoor conditions. Scale is the most persistent and damaging threat overall.
How do I get rid of scale insects on zamia fern?
Brown or tan waxy bumps on fronds and stems; yellowing foliage and sticky honeydew residue Scrape off manually, apply isopropyl alcohol with a cotton swab, or treat with horticultural oil spray; repeat every 2 weeks
How do I get rid of mealybugs on zamia fern?
White cottony clusters in leaf axils and along the rachis; stunted new growth Dab with 70% isopropyl alcohol, spray neem oil solution, or use insecticidal soap; isolate the plant immediately
How do I get rid of cycad blue butterfly (theclinesthes onycha) caterpillars on zamia fern?
Chewed and skeletonized emerging fronds on outdoor specimens Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to new flush growth in spring and summer