What's eating my allium 'globemaster'?

Allium 'Globemaster' is resistant to most pests due to its sulfurous compounds, but allium leaf miner and onion thrips can cause significant damage to foliage. Slugs attack soft emerging shoots. The large bulbs can fall prey to narcissus bulb fly and stem and bulb eelworm in susceptible soils.

Rows of white feeding punctures on leaves; larvae tunnel into stems and bulbs causing rot and plant death. Exclude adults with insect-proof fleece during March–April and October–November flight windows. Destroy infected material.

Soft, distorted, swollen foliage ('bloat'); bulbs rot from within with no obvious external pest visible. No chemical control available in gardens. Remove and destroy affected bulbs; avoid replanting alliums in the same spot for several years.

Silver streaking and flecking on leaf surfaces, reducing photosynthesis and plant vigour. Reflective mulches deter adults; insecticidal soap or neem oil sprays; remove debris where thrips overwinter.