Here at home I refer to leaf miners as “artists” because they make “artwork” on your plant leaves. This may sound like a fun name for these pesky critters, but it’s surely not fun to have these pests living on your plants. The artistic paths these leaf miners create are caused by tunneling larvae. Definitely less fun the more you learn about them, right?

How do Leaf Miners Enter Leaves?

So what kind of larvae is so artistic, you ask? It’s the larvaes of black flies. Eggs are placed on the undersides of leaves. When the eggs hatch, the larvae enter the top and bottom layers of the leaves and they begin to feast in trails.

How Do I Know If I Have Leaf Miners?

You can tell your plant leaves have leaf miners if you notice squiggly lines on your leaves. In many cases, the trails will look lighter in color or even slightly see through, because the leaf miners ate the inside of the leaves along the trails.

Further damage can often be seen as spotted or discolored leaves. Plants that are affected in this way could sow these other symptoms due to underlying factors such as an imbalance in the soil or other stressors which are making them more vulnerable to the bugs.

Some plants that can be affected by leaf miners include:

  • Citrus
  • Tomato
  • Cucumber
  • Chards
  • Spinach
  • Swiss chard
  • Beets
  • Lettuce
  • Eggplants
  • Beans
  • Squash
  • Peppers
  • Peas

How to Control Leaf Miners

The only way to be certain you got rid of leaf miners is you remove the leaves and dispose of them while the miner is still inside. Doing this will prevent the miner from going into other leaves and later prevent it from growing into a black fly which will lay eggs and continue the cycle of invasion.

Leaf miners are difficult to treat since they live inside of leaves. However, another method to try is to spray with neem oil or soap solutions. The problem is insecticide will not eliminate the leaf miner flies if you spray too early or too late since it will not reach either the larvae or the flies. The trick is to figure out when the larvae will turn into black flies so that you know when to spray.

If you’re really driven to get rid of these pests, you can collect leaves with leaf miners inside, place them in a sealed bag or jar, and then spray your affected plants the day you see the flies appear in your bag. This is of course under the assumption all flies will appear the same day, but to be safe you sould spray about three days in a row. If you can eliminate the flies, they will not be able to lay leafminer eggs in the future.