Divisi
Tomato leafminer
Phthorimaea absoluta · Insect
Photo: Marja van der Straten, NVWA Plant Protection Service, Bugwood.org · CC BY 3.0 us
The tomato leafminer (Phthorimaea absoluta, also called Tuta absoluta) is a tiny silvery-grey-brown moth whose caterpillars are one of the most destructive pests of tomato in the world. The moth lays eggs on the leaves, stems and growing tips; the grubs then tunnel inside the leaves, bore into stems and shoots, and burrow into the fruit — always feeding where sprays cannot easily reach. It also attacks potato and pepper, breeds very fast with many overlapping generations a year, and quickly stops responding to chemicals, so it can wreck a whole crop in a single season.
Astronatas · CC BY-SA 4.0 
Metin Gulesci, Leaf Tobacco, Bugwood.org · CC BY 3.0 us
Why it matters
Tomato leafminer is the most dangerous pest of tomato — a bad attack can take almost your whole crop (up to 90%) and leave the fruit tunnelled and unsellable. The grubs feed hidden inside the leaves, stems and fruit, where sprays struggle to reach them, and they breed so fast that they soon stop dying to the chemicals you use. Once it settles into a field it is very hard to clear, so your best chance is to catch it at the very first sign and never let its numbers build.
When to act
Act on the first fresh mines or the first males caught in pheromone traps; because generations are fast and damage escalates quickly, do not wait for heavy mining.
This guidance is general, compiled from published agronomic references including FAO and CABI. Thresholds and timing shift with your crop, your variety and the season.
In much of the region a spray is simply called mushonga — medicine. But a chemical group you cannot name is one you cannot rotate, and a product you did not write down has no pre-harvest interval you can observe. Mushonga, and other farming words →
The full tomato leafminer field guide
- Identify it
- Scout for it
- Control it
16 field-guide sections in the app
The full guide to tomato leafminer — every symptom to check, how and when to walk your field looking for it, and the controls that actually work, ranked. Built into your crop plan, so you are told to look before it costs you a harvest.
Crops it affects
Frequently asked questions
How do I identify tomato leafminer?
The first thing you'll see is pale, see-through blotches or blisters on the leaves. A mine is a hollow the grub eats inside the leaf, between its two skins. Hold a leaf up to the light: a fresh mine looks like a translucent window with tiny dark grains inside — that grit is frass, the grub's droppings. As the mine ages the leaf patch turns brown, dry and papery.
When should I take action against tomato leafminer?
Act on the first fresh mines or the first males caught in pheromone traps; because generations are fast and damage escalates quickly, do not wait for heavy mining.
How do I control tomato leafminer?
Start clean: plant healthy seedlings from a screened, insect-proof nursery — never carry in seedlings that already have mines. Where you can, grow under insect-proof netting to keep the moths off the crop in the first place.
Which crops does tomato leafminer affect?
Among the crops covered here: Tomato.
Catch it before it costs you a harvest
Divisi builds scouting into your crop plan — it tells you when to walk your field, what to look for at that stage, and what to do when you find it. Free for farmers, works offline.
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