Free Tropical Runtz seeds on orders over $150!

1. Leaf Miners on Cannabis Plants

Leaf miners are an extremely annoying pest, one of the trickiest bugs on cannabis – thankfully, this article will be a great resource to anyone dealing with leaf miners.

How to identify leaf miners on cannabis plant

So what are leaf miners? In keeping with its name, cannabis leaf miners sift through leaves. In their wake, a feeding tunnel is left in the form of gnawed-through plants. Your leaf miner cannabis leaves are covered in this pattern, making it very apparent what type of issue you are facing.

Many moths, sawflies, wasps, and beetles lay their eggs in leaf miners, which are the larval stage of many insects. Each species goes through a four-stage life cycle that begins with an egg that hatches into an adult. When they’re hungry larvae, they wreak havoc by mining leaves.

Leaf miner larvae

For various reasons, cannabis leaf miners prefer to eat within the leaves rather than on the surface. To begin with, chowing down on the interior of a leaf fills their stomachs and provides a sanctuary from predators. As a second step, they seek the juicier tissue in plants with less cellulose, a fibrous structural component.

This larval survival technique is harmful to plants, yet it is pretty successful for larvae. Leaf miner invasions that are aggressive may cause severe damage to leaves and negatively impact plant development and output.

What causes leaf miners on cannabis?

Female insects deposit embryos of leaf miners to begin their life cycle. Insect larvae begin tunneling into leaves as soon as they hatch. The larvae gradually transform into pupae and finally into adult insects, assuming they can survive the early stages of life.

Cannabis leaf miner eggs are genetically enhanced by the union of a male and a female wasp, beetle, moth, or sawfly. The most effective way to stop leaf miner damage is to impair the reproductive cycle of these species, even though they all serve a crucial function in the ecosystem.

How to get rid of leaf miners on cannabis?

If you can, get rid of the damaged leaves

Since the bugs are dwelling within the leaves, this won’t solve anything, but it will kill the affected leaf and the bugs that live there. You may crush the larva by pushing your fingers together if you don’t want to take all the leaves.


There are no side effects to Spinosad products, safe and organic for dogs, children, and plants. Leaf miners may be killed by ingesting Spinosad products, which should also be sprayed generously in areas where you see leaf miner damage. Spinosad may or may not be as successful as other therapies, but it does work and is completely safe for plants, animals, and people alike. 

Neem Oil

Most organic farmers keep a bottle of neem oil in their greenhouses and grow rooms. Triterpenoid chemicals found in neem oil, extracted from the fruits and seeds of an evergreen tree native to the Indian subcontinent, are effective against insects and fungi. Neem oil, an organic insecticide, effectively keeps pests like leaf miners away while not harming beneficial insects and worms. After just a few applications, the oil will eliminate leaf miners from your leaves.

In a mister, combine one teaspoon of neem oil with one liter of warm water. The oil and water will mix better if you add five drops of surfactant. Shake the mister and spray the fan leaves of all the damaged plants with the water left behind. Although neem oil is effective against specific pests, there are drawbacks to using it. For some people, the oil might linger for a long time and cause a bad taste in their mouths. Use this treatment only while the plant is in the vegetative stage before the flowers begin to blossom.

BT Spray – if moth/caterpillars are the culprits

Some moths deposit eggs that hatch into leaf-tunneling larva, transforming into caterpillars, transforming into a moth of its kind. You should use BT spray right once if you see leaf miner damage and indications of moths or caterpillars on your plants (such as anything eating on your leaves, small black droppings, or a worm in the act).

In this biological pesticide, the bacillus thuringiensis (BT) bacterium kills larva and stops caterpillars from eating. Using this method, you may destroy caterpillars and their larva without harming helpful insects. It also kills fungus gnats and worms in the cannabis plant as a bonus. Use a caterpillar BT spray once you notice leaf miner damage and caterpillars or caterpillar dung.

Beneficial Insect Predators

Diglyphus Isaea, a species of parasitic wasp, is a leafminer’s worst enemy and can cheerfully devour them. If you’d want to assist limit the population of leaf miners by using nature’s insecticide, you may purchase them online.

Floating coverings for the cannabis rows

Not all cannabis producers will benefit from them; however, they are inexpensive and excellent in keeping leaf miners away from your plants while allowing light to reach them. You may also use the netting to water your plants. Some growers use them to create tiny “green homes” for their plants, but since they’re so light and airy, the plants don’t seem to mind when they’re draped over them.

Dealing with leaf miners outdoors 

Pesticides are useless to remove these pests because the plants themselves protect them. The simplest and most effective solution is to smash the larvae in their tunnel and remove any impacted leaves. Learn how to get rid of leaf miners home remedies as soon as possible.

A parasitic wasp that feeds on the larvae of leaf miners might also be used to remove large numbers of the pests at once. Adult flies will be attracted to the yellow adhesive tape, which will kill them if you get it from your local garden center.

Stop leaf miners before they become a problem

Preventative measures are the best way to keep leaf miners away from your cannabis production. Install row coverings just in case, especially if you’ve had previous attacks or heard about them from nearby producers.

You should attempt the treatments mentioned above as soon as possible if you have detected the dreaded white trials midway through the growing season. After a few days, you’ll be back on track.

Picture of Ed Rushford

Ed Rushford

Ed Rushford’s impact on cannabis growing is undeniable. Though he tends to focus primarily on 2 areas, plant training techniques and dealing with disease, pests, and other problems, he has offered many insights into how cannabis plants live and grow. That’s not to say that Ed is unfamiliar with the complete life cycle of cannabis, from seed to harvest, but he uses his widespread knowledge to hone in on the minutia and niche areas of growing cannabis. Ed’s goal is to spread knowledge and allow for everyone to become better growers. 𝕏

Shop popular cannabis strains

Here's 20% Off On Us!

We want to help you get your hands on the seeds you want, take 20% off your next purchase when you enter your email below!

Here's 20% OFF On Us!

We want to help you get your hands on the seeds you want, take 20% off your next purchase when you enter your email below!