Troubleshooting
Allium 'Globemaster' problems — and how to fix them
Allium 'Globemaster' (Allium 'Globemaster') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Bulb rot in wet ground
The heavy bulbs are prone to rotting in cold, waterlogged or summer-wet soil. Sharp drainage and a dry dormancy are non-negotiable; plant on grit and avoid irrigating in summer.
Untidy fading foliage
The broad basal leaves yellow and collapse as the flowers open. Interplant with later perennials or grasses to mask the declining foliage.
Allium leaf miner / onion fly
Larvae mining the leaves and bulb cause distortion and create rot entry points. Use fine insect mesh over emerging growth during adult flight periods in affected areas.
Top-heavy stems flopping
The huge heads can lean if grown soft in shade or rich nitrogen. Full sun and lean feeding produce the sturdy stems needed to hold the globes upright.
Prevent allium 'globemaster' problems before they start
Most allium 'globemaster' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for allium 'globemaster' in general rather than its problems? Read the full allium 'globemaster' care guide — light, water, soil and feeding.
Allium 'Globemaster' problems — FAQ
Why is my allium 'globemaster' bulb rot in wet ground?
The heavy bulbs are prone to rotting in cold, waterlogged or summer-wet soil. Sharp drainage and a dry dormancy are non-negotiable; plant on grit and avoid irrigating in summer.
Why is my allium 'globemaster' untidy fading foliage?
The broad basal leaves yellow and collapse as the flowers open. Interplant with later perennials or grasses to mask the declining foliage.
Why is my allium 'globemaster' allium leaf miner / onion fly?
Larvae mining the leaves and bulb cause distortion and create rot entry points. Use fine insect mesh over emerging growth during adult flight periods in affected areas.
Why is my allium 'globemaster' top-heavy stems flopping?
The huge heads can lean if grown soft in shade or rich nitrogen. Full sun and lean feeding produce the sturdy stems needed to hold the globes upright.