Heuchera 'Miracle' problems — and how to fix them

Over-watering or poorly drained soil causes fatal crown rot; plant at the correct depth with free-draining soil and avoid mulching over the crown.

Notched leaf margins signal adult weevils; larvae in the root zone are more damaging — drench with nematodes in late summer as a targeted treatment.

Grey mould thrives in cool, damp, crowded conditions; thin planting, remove dead foliage, and improve airflow to reduce incidence.

Hot, dry, sunny positions bleach the amber tones and scorch edges; transplant to a more sheltered, shadier spot if persistent.

Newly emerged spring foliage is vulnerable to slug damage; use wildlife-safe pellets or grit barriers around the plant base.