Leaf miners
PEST
When it's active · UK
JFMAMJJASOND
When it's active · Northern Italy
JFMAMJJASOND
When it's active · Central Italy
JFMAMJJASOND
When it's active · Southern Italy and islands
JFMAMJJASOND
How to recognise it
Pale, winding or blotchy tunnels visible within the leaf tissue itself, distinct from surface feeding damage.
Life cycle and conditions
Larvae of various small flies or moths tunnel inside the leaf; several genus-specific leaf miners occur in UK gardens, including on delphiniums and box.
Prevention
Remove and dispose of affected leaves promptly to break the lifecycle before larvae complete development.
How to treat it
🌿 ORGANIC · RECOMMENDED
Picking off and disposing of mined leaves promptly is usually sufficient to break the lifecycle before larvae complete development.
🧪 CHEMICAL · IF YOU CHOOSE
Chemical treatment is rarely necessary or practical for leaf miners, since the larvae are protected inside the leaf tissue — removal is both simpler and more reliable.
PLANTS MOST AFFECTED