What's eating my athyrium niponicum 'red beauty'?

Japanese painted ferns like 'Red Beauty' grown outdoors are most troubled by slugs that shred delicate fronds, and by aphids on soft new growth. Vine weevil grubs attack roots in containers. Deer will browse fronds if hungry. Indoors or in sheltered spots, spider mites can occur in dry conditions.

Ragged holes in unfurling croziers and frond pinnae, worst during cool, moist periods Use ferric phosphate pellets; set beer traps; hand-pick at night; clear leaf litter around crowns

Sticky honeydew on fronds, distorted or yellowing new growth, possible sooty mold development Knock off with a water jet; apply insecticidal soap; introduce natural predators such as lacewing larvae

Adult notching on frond edges; larvae cause wilting by destroying roots and crown Apply nematodes (Steinernema kraussei) to moist compost in late summer or early autumn

Fronds browsed down to stubs, especially in late winter when other food is scarce Use deer repellent sprays or physical fencing; plant among deer-resistant species as a deterrent