What's eating my hardy geranium 'rozanne'?

Geranium 'Rozanne' is troubled mainly by capsid bugs, which cause distinctive tiny holes and distorted leaves in early summer, and vine weevil in containers. Slugs and snails target young spring growth. Sawfly larvae can strip leaves in summer. Deer may occasionally browse it but rabbits tend to avoid it.

Root-feeding white larvae hollow out fleshy crowns and roots, causing plants — especially pot-grown specimens — to collapse and die; adults notch leaf margins at night. Apply pathogenic nematodes (Steinernema kraussei) to moist soil in late summer. Use vine weevil barrier tape on pots. Inspect roots at division time and destroy grubs.

Distinctive pin-prick holes and tattered appearance in young leaves from May–July as toxins injected during feeding cause tissue to collapse; growing tips may be distorted. Difficult to control as capsids move quickly. Remove overwintering egg sites (weedy vegetation). A pyrethrin or deltamethrin spray in evening when bugs are active can reduce numbers.

Irregular holes in young foliage emerging in spring, with slime trails; worst in mild, wet springs when growth is lush and soft. Apply ferric phosphate pellets around crowns in spring. Hand-pick at dusk. Copper tape on pots. Established plants recover well from slug feeding.

Caterpillar-like green larvae skeletonise or completely strip leaflets in late spring and summer, working outward from the leaf margins. Hand-pick larvae and egg clusters from undersides of leaves. For heavy infestations, use an insecticide approved for caterpillars/sawfly (e.g., pyrethrin) in the evening.