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Leaf miners: those squiggly lines on your leaves
Pale, wandering tunnels all over your spinach and tomato leaves? Leaf miners. Mostly cosmetic, easily managed — here’s how, and when not to worry.
Leaf miners are the tiny larvae of small flies that live and feed between the upper and lower surfaces of a leaf, carving those distinctive pale, squiggly tunnels as they go. Spinach, tomato, brinjal, beans, gourds and citrus are common hosts.
Here’s the key thing most panic-Googling gardeners need to hear: leaf miner damage is usually just cosmetic. Unless an outbreak is severe and widespread, the plant carries on perfectly well. Squish the tunnels, remove the worst leaves, hang a few traps, and save your energy for pests that actually matter.
Squish the tunnels
The grub is inside the leaf at the end of the squiggle. Pinch along the tunnel between your fingers and you squash it — oddly satisfying, completely free.
Remove badly mined leaves
Pick off and bin leaves that are heavily tunnelled. Don’t strip the whole plant — a few miners do little real harm.
Hang sticky traps
Yellow and blue sticky traps catch the adult flies before they lay the next generation.
Disrupt them with neem
A 10% neem oil spray disrupts the miners’ life cycle. Repeat through the cycle rather than expecting one hit to do it.
Grow strong plants
Healthy, well-fed plants shrug off cosmetic miner damage easily. Vigour is half the defence.
Frequently asked questions
Are leaf miners harmful to my plants?
Usually not. The squiggly tunnels are mostly cosmetic damage; plants keep producing fine unless an outbreak is severe and widespread.
How do I get rid of leaf miners naturally?
Squish the larvae inside the tunnels, remove badly affected leaves, hang yellow/blue sticky traps for the adult flies, and spray a 10% neem solution to disrupt their life cycle.
Which plants get leaf miners?
Spinach, tomato, brinjal, beans, gourds and citrus are common hosts.