What's eating my ninja tiarella?

Ninja Tiarella, with its dramatic dark-centered leaves, is vulnerable to the same pests as other Tiarella cultivars. Black vine weevil larvae pose the greatest risk, silently destroying roots. Slugs attack soft new foliage, particularly in spring. Foliar nematodes can cause angular brown leaf patches. Late-summer nematode drenches are the most effective control.

Notched leaf margins (adult feeding); root and crown destruction by soil-dwelling larvae — the plant wilts and collapses with no above-ground warning Drench moist soil with pathogenic nematodes (Steinernema kraussei or Heterorhabditis megidis) in August–September; hand-remove adults after dark; inspect crowns of declining plants

Irregular holes through the ornamental, dark-marked leaves; young plants and new spring growth most at risk Use iron phosphate slug bait in spring and after wet weather; set beer traps; hand-pick in the evening; avoid overcrowded, overly damp planting conditions

Angular, between-vein brown or yellow patches on leaves; spreads through water splash, progressing up the plant and between nearby plants Destroy all affected material; water only at the base; do not compost affected leaves; source replacement plants from disease-free stock