Pest identification
What's eating my holmgren's dioon?
Armored scale (Diaspididae)
Signs: Hard waxy shells clustered on stems and frond undersides; frond yellowing, honeydew secretions
Control: Scrape off scales manually; apply horticultural oil or systemic imidacloprid drench; recheck after 2–3 weeks
Mealybugs (Pseudococcus spp.)
Signs: White cottony deposits in crown and leaf axils; weakened growth and sticky leaf surfaces
Control: Dab with isopropyl alcohol; follow with insecticidal soap or neem oil spray every 7–10 days
Spider mites (Tetranychus urticae)
Signs: Tiny pale flecks and fine webbing on leaflets; accelerated by low humidity
Control: Boost humidity; rinse foliage; apply neem oil or miticide; repeat weekly until resolved
Keep holmgren's dioon pest-free
Healthy plants resist pests best. Get the basics right:
Holmgren's Dioon pests — FAQ
What is eating my holmgren's dioon?
Holmgren's Dioon is a critically rare cycad from Mexico, typically grown indoors or in specialist collections. Scale insects are the primary threat, attaching to the caudex and fronds. Mealybugs and spider mites round out the main pest complex in warm, dry indoor environments. Early detection is critical for this irreplaceable specimen.
How do I get rid of armored scale (diaspididae) on holmgren's dioon?
Hard waxy shells clustered on stems and frond undersides; frond yellowing, honeydew secretions Scrape off scales manually; apply horticultural oil or systemic imidacloprid drench; recheck after 2–3 weeks
How do I get rid of mealybugs (pseudococcus spp.) on holmgren's dioon?
White cottony deposits in crown and leaf axils; weakened growth and sticky leaf surfaces Dab with isopropyl alcohol; follow with insecticidal soap or neem oil spray every 7–10 days
How do I get rid of spider mites (tetranychus urticae) on holmgren's dioon?
Tiny pale flecks and fine webbing on leaflets; accelerated by low humidity Boost humidity; rinse foliage; apply neem oil or miticide; repeat weekly until resolved