What's eating my wall rue?

Wall Rue (Asplenium ruta-muraria) is a tiny crevice-dwelling fern that grows in walls and rocky limestone. Slugs and snails are its main pest threat, especially in garden cultivation where it lacks the natural protection of rock. Vine weevil can attack container-grown plants. Aspleniums as a group are noted as more slug-susceptible than most ferns.

Fronds nibbled down to the stipe or entirely consumed; small rosettes can be wiped out before they establish, particularly in moist, shaded garden spots Grow in wall crevices or raised gritty conditions where slugs are less active; apply iron phosphate pellets or Phasmarhabditis nematodes; sharp grit around the base creates a deterrent barrier

Adults notch the small fronds at night; larvae eat rhizomes in containers, killing small plants quickly given their limited root mass Apply nematodes (Steinernema kraussei) to pots in late summer; inspect root zone regularly in autumn; avoid keeping plants in wooden containers where adult weevils shelter