Observation and action checklist
Pale blotches inside Swiss chard leaves
Inspect both leaf surfaces and the tissue between them, then track whether fresh leaves develop new mines.
Compare what you can see
Pale tissue looks like a pocket between leaf surfaces
Inspect it in good light for a larva or dark material inside. Photograph the mine and the underside separately.
You find mines containing larvae
Remove and destroy the affected leaves or pinch the mined tissue to crush larvae, following the extension guidance. Record which leaves you treated.
The marks are surface spots or open chewing holes
Keep the cause unresolved. Compare other damage signs and request local identification before using a leafminer response.
Your next care visit
Check off what you have reviewed. Use the downloadable sheet to keep your observations.
Choose an older damaged leaf and a newer leaf. Record their positions so you can compare a fresh sample on the next visit.
Check for small white eggs as well as visible mines. Note what you actually see, including an empty result, rather than recording a guessed insect name.
Write down the number of leaves removed or mines pinched. Photograph the plant afterward so later damage is not confused with today's marks.
0 of 3 steps reviewed
Keep this in mind
Do not apply a general insect spray based on pale patches. Beneficial insects attack leafminers, and sprays can interfere with them.
What to record next
Inspect the newer leaves on your next visit. Count fresh mines separately from older marked tissue. If the signs still do not match, keep photographs for a local plant clinic.
- Date and sampled leaf positions
- Blotch shape and appearance
- Underside eggs seen or not seen
- Larvae or dark material inside mines
- Leaves removed or mines pinched
- Next visit: fresh mines on newer leaves
References and scope
Use these extension references to compare symptoms and check crop care. Match planting advice to your variety and local growing conditions.
Reviewed October 21, 2026.
More care tasks
Beet
Several beet seedlings coming from one sowing spot
Count individual stems, check the seed type and make space for the roots you want to keep.
Vegetable containers
A vegetable pot stays wet: check where the water can leave
Identify the container design, inspect moisture below the surface and record drainage before adding more water or rebuilding the pot.