On a bright and sunny morning, you go to check on your plants, only to spot leaf miners. Instead of healthy growth, you find them looking wilted or marked by slimy, white, wavy lines or trails [1].
Those are the signs that the eggs of leaf miner flies that have been nestling snugly inside your plants’ leaves have developed into larvae. At this point, figuring out how to get rid of them is vital.
The maggots are now busy feeding on the sap, forming tunnels along the lines of the leaves of the plants. Therefore, it’s time to take action before an infestation begins.
Here’s how to get rid of leaf miners naturally: These are home remedies and organic solutions to help keep these plant pests away.
1. Beneficial Insects
There are many helpful bugs and insects in the garden that enjoy feasting on destructive insects.
Ladybugs (lady beetles), lacewings, and other useful insects help in the biological control of harmful insects. Leaf miner predators include parasitic wasps in the genus Diglyphus, soldier beetles, and predatory bugs.
2. Hot Pepper Spray
This is a great home remedy for leaf miners on tomatoes, basil, pepper plants, Swiss chard, and other vegetables. You’ll come across various recipes for this on the internet, but we have one that’s fairly easy to make.
To make a simple pepper spray for leafminers, blend 2 hot peppers, 1 onion, and 1 bulb of garlic in a quart of water.
Let the mixture sit for about an hour before straining. Afterward, add a tablespoon of organic liquid soap and shake well.
Use this DIY leaf miner control spray to coat your plants, including the underside of the leaves.
3. Neem Oil
Widely used in organic farming today, neem oil is effective in controlling many insect pests, including leafminers [2].
To use neem oil for leaf miners, make a spray by mixing 2 tablespoons of neem oil with a gallon of water. Shake well and spray the solution on the affected plants.
You can also use this organic pesticide to control insect pests in general and to prevent or kill fungus on your plants.
4. Row Covers
Row covers protect young plants from harmful insects. They also provide protection from birds, domestic pets, night frosts, and daytime sun damage.
You can buy row covers or construct homemade ones from fine mesh or other suitable lightweight fabrics. Remove the covers once the growing season is over.
5. Till the Soil
This is one simple measure to protect your plants from an infestation.
Tilling the soil after harvest can destroy any pupae in the soil. Also, it can prevent adult flies from emerging in the spring.
6. Sticky Traps
An old way of effectively dealing with annoying garden insects is to use sticky traps. These colored strips of sticky material attract pests that become stuck and are unable to mate, lay eggs, or survive.
Sticky traps are particularly useful when hung in greenhouses or near indoor plants.
Different colors attract different pests. However, use yellow or blue for the leaf miner fly.
7. Remove the Eggs
Removing leaves with leaf miner eggs at the outset of any sign of the pests may be tedious but also effective.
8. Spinosad
Another product you can use to get rid of leaf miners organically is Spinosad. Spray it on the leaves for direct contact with the critters.
This garden insect spray paralyzes leafminers and kills them in a day or two. However, you may need more than one application in a growing season.
If you have concerns about the toxicity of Spinosad, manufacturers state that it has low toxicity for mammals. However, it may be harmful to bees.
Therefore, evening spraying or zero spraying in the flowering period of plants may make this leafminer treatment more useful.
9. Beneficial Nematodes
This one is increasingly popular in organic pest control, and it also works for the treatment of leaf miners in the soil. Beneficial nematodes are tiny organisms that occur naturally in the soil.
These microscopic roundworms are capable of destroying many garden pests at their developmental stage in the soil.
Nematodes act by entering the gut of the insect and releasing bacteria that cause blood poisoning and death. They then feed off the dead matter until no further food is available, obliging them to seek new hosts to kill.
Moreover, the constant food source causes the nematodes to grow and multiply, naturally breaking the cycle of infestation.
10. Parasitic Wasps
Some species of parasitic wasps, including Diglyphus isaea, attack and kill leaf miners.
Female parasitic wasps lay their eggs on or inside fly larvae or pupae. After hatching out, the wasp larvae feed on the host larvae.
Plant dill, yarrow, zinnias, and fennel to attract parasitic wasps. You can also purchase Diglyphus isaea from reputable suppliers.
11. Diatomaceous Earth
Diatomaceous earth is processed in a way that causes dehydration in most insects. As a result, it works great as a leafminer control remedy.
Make it into a homemade leaf miner spray or use it in powder form by dusting it on the leaves. However, one point to consider is that a shower of rain will mean reapplication.
12. Trap Crops
Trap crops are grown to lure various pests away from the main plants and crops. As such, they are sometimes called ‘sacrificial’ plants.
Trap crops for the leaf miner insect include columbine, chickweed, lamb’s quarters, velvetleaf, and plantain. Moreover, companion planting with marigolds and garlic can deter these insects.
13. Pruning
This DIY method works best for trees like citrus. Pruning will greatly assist in keeping your plants healthy and enable early detection of any possible infestation.
You can then remove and dispose of the infected leaves. You may also frequently find these leaf worms on boxwoods.
14. Vinegar
A spray made of one part vinegar and three parts water can be used to help deter adult flies from laying eggs. Spray it on affected (and those likely to get affected) plant leaves.
15. Baking Soda Spray
Baking soda is useful in protecting plants from certain pests and fungus attacks.
To use baking soda for leaf miners, combine one tablespoon of baking soda with a tablespoon of dish soap in a gallon of water.
Shake well and use it to spray your plants.
Damage
Damage mainly appears as tunnels and pale white, curvy lines on plant leaves.
Plants that leaf miners attack include spinach, basil, beets, Swiss chard, tomato plants, lettuce, and other vegetables. They also go after pigweed, lamb’s quarters, and other weeds.
Takeaway
It is so disheartening to spend time and effort producing fine plants only to suffer leaf miner damage.
Commercial leaf miner pesticides are available, but fortunately, as you can see, there are also many solutions to control the critters organically.
How often do you apply Neem Oil to tomatoes to get rid of active Leaf Miners?
Apply once a week until it clears up.