Pest identification
What's eating my red tropea onion?
Onion fly (Delia antiqua)
Signs: White maggots tunnel into the base of bulbs and roots; plants yellow, wilt, and rot from the ground up
Control: Row cover from planting; avoid sets in ground previously cropped with alliums; burn or bin infected plants
Onion thrips (Thrips tabaci)
Signs: Silvery stippling and streaking on leaf surfaces; heavy infestations cause leaf tips to die back
Control: Insecticidal soap spray; reflective mulch to disorient adults; maintain moisture to reduce plant stress
Allium leaf miner (Phytomyza gymnostoma)
Signs: Rows of white feeding punctures on leaves; larvae tunnel to base and create entry for soft rot bacteria
Control: Fine-mesh insect net during spring and autumn adult flight periods; remove and destroy affected plants promptly
Birds (rooks, starlings)
Signs: Newly planted sets pulled from soil by birds investigating the fresh earth
Control: Cover sets with fleece or netting for the first 2–3 weeks after planting until roots anchor the bulbs
Keep red tropea onion pest-free
Healthy plants resist pests best. Get the basics right:
Red Tropea Onion pests — FAQ
What is eating my red tropea onion?
Red Tropea onion is a mild, elongated Italian variety that faces the same Allium pest complex as all garden onions. Onion fly is the most destructive pest, with larvae destroying bulbs underground. Thrips scar foliage and reduce photosynthesis. Allium leaf miner has spread widely in the UK and US. Birds may pull newly planted sets.
How do I get rid of onion fly (delia antiqua) on red tropea onion?
White maggots tunnel into the base of bulbs and roots; plants yellow, wilt, and rot from the ground up Row cover from planting; avoid sets in ground previously cropped with alliums; burn or bin infected plants
How do I get rid of onion thrips (thrips tabaci) on red tropea onion?
Silvery stippling and streaking on leaf surfaces; heavy infestations cause leaf tips to die back Insecticidal soap spray; reflective mulch to disorient adults; maintain moisture to reduce plant stress
How do I get rid of allium leaf miner (phytomyza gymnostoma) on red tropea onion?
Rows of white feeding punctures on leaves; larvae tunnel to base and create entry for soft rot bacteria Fine-mesh insect net during spring and autumn adult flight periods; remove and destroy affected plants promptly
How do I get rid of birds (rooks, starlings) on red tropea onion?
Newly planted sets pulled from soil by birds investigating the fresh earth Cover sets with fleece or netting for the first 2–3 weeks after planting until roots anchor the bulbs