Leaf miners on marijuana plants

Leaf miners are a type of insect that has a unique style of damaging your marijuana plants: they burrow between the two epidural layers of your plants’ leaves, eating the plant cells along the way. Adult leaf miners are a type of fly, and they look similar to a house fly.

They are not the culprits for the burrowing damage, however. Instead, they lay eggs on the bottom side of your plants’ leaves. Once those eggs hatch, the resulting larvae are what then begin eating and burrowing on the leaves.

Leaf miners are always the larvae version of their adult counterparts. While flies are the most common, you might also see leaf miners that come from moths, beetles, or sawflies.

Signs of leaf miners

Their presence is obvious because they leave a squiggly line the whole way that is white or brown in color. This pattern sits on top of the leaves of your marijuana plants, making it really clear what kind of problem you are dealing with.

Signs of leaf miners
Signs of leaf miners

Their presence is obvious because they leave a squiggly line the whole way that is white or brown in color. This pattern sits on top of the leaves of your marijuana plants, making it really clear what kind of problem you are dealing with.

Although you may lose a couple of leaves here and there, leaf miners don’t pose too high of a threat to your plants’ total health. Generally, their populations stay low and the injuries to your plants are quite minimal.

A complete plant defense system can help protect your crop from diseases and harmful pests. Grab our Plant Protector set today!

Marijuana Plant Protector Set

Buy plant protector set

  • Protection against diseases and pests
  • Consists of three 20 ml bottles
  • Enough plant protection for 20 plants

Not sure if leaf miners are causing the damage to your marijuana plants?

Also read the article “Marijuana pest and bug control” for a list with pictures of all pests and bugs

How to get rid of leaf miners

Pesticides won’t work against these pesky creatures, simply because they are protected by the plant’s own skin. Your best bet is, therefore, to simply squish the little maggots within their burrow, then remove the leaves that were affected.

How to get rid of leaf miners
How to get rid of leaf miners

Another option to eradicate lots of leaf miners at once is to bring in a parasitic wasp that will consume these larvae. You can also purchase yellow sticky tape at your local garden center, which will attract the adult flies and they will then get stuck there and die. You can buy the yellow sticky tape online at this link.

List of marijuana plant symptoms

  • Squiggly gray or brown lines on leaves
  • Presence of flies
  • Eggs on leaf underside
  • Larvae on leaf underside
  • Leaf death
  • Dry patches on leaf

While they are a bit of an annoyance and may damage some leaves, leafminers are generally not a huge threat to marijuana growers. You should take care of the problem as described above, but don’t panic about your crops and the end yield – they will probably be relatively unaffected.

Plants with strong genetics have less chances of getting sick and are less vulnerable to pests and diseases. I have created multiple grow sets which features all you need in order to grow healthy plants from seed to harvest!

buy Gold Leaf marijuana strain grow kit

Marijuana grow set

Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible

Happy growing!


Avatar for Robert Bergman

Mr Robert Bergman PhD


Robert Bergman is an Amsterdam-based marijuana grow expert who has years of experience from small grows to massive operations ... See profile

  • Pinterest

13 comments on “Leaf miners on marijuana plants”

  1. As always, thank you for your help. Your seed is AMAZING THIS YEAR ‘LITTLE MONSTER’S AS lady gaga would say.HA! Luv & Peace, sandi

  2. forestfisherman,

    Have you tried insecticidal soap safe for vegetables? A common remedy is to make a pepper spray. There are many recipes. (water a hot pepper, some citrus. Bugs hate citrus, and I am forgetting something but, you can do a search and find all kinds of articles and topics about pepper sprays.

    Good Luck 🙂

  3. I have A bad problem with Leaf Miners. Only thing that seems to help is, spray them every other day with Neem Oil. If I spray them in the morning, I see the egg layers on my plant by noon.
    Any Sugestions?

  4. I downloaded the grow bible not so long ago after encountering a number of issues, be it from poor growth to nutrient deficiencies to pests and I have to admit that I will never regret my choice to download it…

  5. caterpillars shrink and move on when youuse on them ,COMPO “Orchideendüngen” Orchid fertilizer.


  7. […] Unfortunately, leaf miners are extremely difficult to get rid of. Pesticides are mostly ineffective against them, and the ones that do work aren’t safe to use on your plants: they’re more harmful than helpful. The only thing to do is seek them out and squish them yourself. Read more about Leaf miners on marijuana plants […]

  8. I really like this symptom checker. very informative. It really helps those question marks in the back of my head.