Pest identification
What's eating my petrocosmea iodioides?
Mealybugs
Signs: Cottony white deposits at leaf bases and in the crown; honeydew and sooty mould; stunted new growth.
Control: Spot-treat with isopropyl alcohol on a swab; follow up with neem oil spray every 7-10 days; quarantine the plant away from others.
Spider mites
Signs: Stippled, dull foliage with silvery-bronze patches; fine webbing visible on undersides in dry conditions.
Control: Mist surroundings to raise humidity (avoid misting hairy leaves directly); apply insecticidal soap to undersides of leaves every 5-7 days.
Fungus gnats
Signs: Larvae consume root hairs, reducing vigour; adults indicate chronically wet soil.
Control: Improve drainage and allow the topsoil to dry; use Bti-based biological drenches; yellow sticky cards monitor adult numbers.
Keep petrocosmea iodioides pest-free
Healthy plants resist pests best. Get the basics right:
Petrocosmea iodioides pests — FAQ
What is eating my petrocosmea iodioides?
Petrocosmea iodioides is a compact, hairy-leaved indoor gesneriad prized for its violet-blue flowers. Like all Petrocosmea, it is most troubled by mealybugs sheltering in the dense rosette and by spider mites in low humidity. Fungus gnats can become a problem if soil stays too wet between waterings.
How do I get rid of mealybugs on petrocosmea iodioides?
Cottony white deposits at leaf bases and in the crown; honeydew and sooty mould; stunted new growth. Spot-treat with isopropyl alcohol on a swab; follow up with neem oil spray every 7-10 days; quarantine the plant away from others.
How do I get rid of spider mites on petrocosmea iodioides?
Stippled, dull foliage with silvery-bronze patches; fine webbing visible on undersides in dry conditions. Mist surroundings to raise humidity (avoid misting hairy leaves directly); apply insecticidal soap to undersides of leaves every 5-7 days.
How do I get rid of fungus gnats on petrocosmea iodioides?
Larvae consume root hairs, reducing vigour; adults indicate chronically wet soil. Improve drainage and allow the topsoil to dry; use Bti-based biological drenches; yellow sticky cards monitor adult numbers.