What's eating my coral bells 'obsidian'?

Coral Bells 'Obsidian' shares the same pest profile as other Heucheras: the biggest threat is black vine weevil, whose larvae devour roots underground while adults notch leaves at night. Mealybugs and foliar nematodes are secondary concerns. Otherwise it is a low-maintenance, largely trouble-free perennial.

Characteristic half-moon notches cut into leaf margins by adults; larvae hollow out roots and crowns, causing sudden collapse, especially visible in spring. Apply pathogenic nematodes to damp soil in late summer; adult feeding on foliage at night can be reduced with an evening spray of acephate or azadirachtin.

Cottony white clusters at leaf bases and stem joints drain plant sap, leading to stunted, distorted growth. Spot-treat with rubbing alcohol on a cotton swab; follow up with insecticidal soap spray every 5–7 days until clear.

Linear yellow-to-brown lesions running parallel to leaf veins; severely affected leaves dry out and become papery. Remove infected foliage immediately and dispose in waste (not compost); avoid wetting leaves when watering and increase plant spacing for airflow.