Common Cannabis Pests and How to Deal With Them

11 Sep 2019
Fungus gnats are an example of cannabis pests

Beginning your adventure with growing marijuana plants at home may not be that easy a task. Especially when it comes to fighting common cannabis pests. For the record, pests are like cops; the moment they get their hands on your plants, you’re screwed – and that’s a beautiful yet sad metaphor, isn’t it?

Pests on cannabis

Source: 420 Light Guide

Well, dealing with cannabis pests can become a pain in the neck – that we already know. But dealing with those insects is one thing. Preventing them from ever appearing on your cannabis plant is another. Given this, before we elaborate on different ways to combat the unwelcome guests, let’s get to know these guys in the first place.

Most Common Marijuana Pests

The list of natural threats to your cannabis plant is quite long, to be honest. However, we distinguish a couple of particularly persistent pests that can really go hard on your future harvest.


Aphids on marijuana

Source: Wikipedia

Aphids are characterized by their pale yellow color. They’re known for being one of the most annoying pests a marijuana grower can ever confront. These insects reproduce like crazy, not to mention they’re easy to miss before they become a plague. Aphids typically feed on marijuana leaves by taking its nutrients away, which may ruin the entire harvest. Watch out for them, especially when growing weed indoors.

Spider Mites

Spider mites on marijuana

Source: Native Land Design

Similar to aphids, spider mites have a rapid reproduction rate. Being the nightmare of rookie growers, spider mites can quickly wreak havoc on your crops and can discourage you from even thinking of growing cannabis again. These insects love humid places. If you’re growing marijuana indoors, it’s of utmost importance to check for their presence on a regular basis.

When you see white, yellow, or black spots showing up on the leaves, it’s an indicator that spider mites have started spreading. The fact that they are sticky and extremely difficult to get rid of doesn’t make the situation better. Once you spot a spider mite, act as quickly as possible. Because if you give them time to spread, they will kill your cannabis overnight.

Fungus Gnats

Fungus gnats are a one of my cannabis pests

Source: This Natural Dream

Although the Latin name for these insects could suggest an exotic meal or some similar stuff, the reality is a far cry from your initial guess.

Also known as soil gnats, fungus gnats are about 4-5mm wide and they occupy both the lower areas of your plant and the soil’s surface. These insects are rather easy to spot; simply look for larvas with a dark head and transparent body. Fungus gnats can be typically found at the first few centimeters of your plant’s base because they like moist areas.

Despite being less destructive than spider mites and aphids, soil gnats can still cause serious damage to your crops – this applies to roots and stems, too. These insects aren’t picky, they just devour the plant entirely starting from the base and finishing in the very root system. The moment you notice your plant is growing slower than before, look for these larvas and don’t neglect the danger.

How to Deal With Marijuana Pests Without Harming the Environment?

Ladybugs on marijuana

Source: The Stranger

Being a marijuana grower leaves you with two paths to follow in order to get rid of the aforementioned cannabis pests. You can become an organic grower and minimize the danger of pests without using artificial solutions. Or, you can draw out big guns and take the risk of consuming these chemicals with the smoke once your buds are cured, dried and ready for use.

Needless to say, we want to contribute to our environment and provide hints for healthy weed options. So we’re going to focus on organic pest control.

Integrated Pest Management (IPM)

Integrated pest management aims at retaining full control over the pest population on your cannabis plant with nothing but organic solutions.

The IPM system involves a number of strategies any grower should apply to deal with marijuana pests and prevent their occurrence. You may very well use fragrant oils (peppermint and cinnamon are great) or foliar sprays to protect your crops against insects.

Some people go even further by creating an ecosystem for the grow room with companion planting. Extra plants in the growing area serve as a strong shield against the unwelcome guests.

Other growers take their creativity to an entirely new level by purchasing predatory mites that control other pests. Keep in mind, though, that this method is not suitable for newbies, as it requires more in-depth knowledge about predatory mites and the way they interact with other insects.

Simpler Methods, Please?

Cinnamon as answer to controlling cannabis pests

Source: Chowhound

Okay, I have good news for those of you who want to keep things simple. You can easily make a DIY organic pesticide by placing one teaspoon of cinnamon in a dish filled with one-quart water and mixing everything together. Then, you’re free to spray the substance on your plants to create a natural barrier against common marijuana pests.

On the other hand, if you aim at making a more advanced organic pesticide, add cinnamon tea or pure Castile oil to the initial mixture. You can use it interchangeably with a mixture of water and pressed garlic. Garlic comes with a plethora of benefits for our bodies, but you may very well use it on the cannabis plant as well. However, it’s best to keep the use in moderation; otherwise, it may kill the good insects as well.

Another natural ingredient that proves invaluable for dealing with common cannabis pests is cloves. Cloves are very effective in terms of the plant protection, so if you want to keep your crops clean and healthy, prepare a mixture of cloves and a couple of drops of essential oils like citrus or peppermint. The aroma of cloves keeps aphids, spider mites, and ants away.

Last but not least, use your preferred mix to the new growth at the very beginning to protect you to prevent cannabis pests from appearing.

Other Organic Solutions for Cannabis Pest Control

Keeping your marijuana plants clean and safe is paramount for drawing the maximum yields from your harvest. If you’re not into the DIY thing, take a look at these commercial organic pesticide solutions.

Insecticidal Soap

Insecticidal soap is useful in fighting spider mites, scales, thrips, and aphids. Simply use about five tablespoons of the product for a gallon of water and combine the ingredients thoroughly. Once you’re through, spray the mixture onto any insects. Most of all, remember to rinse your buds if you use the soap while your plant goes through the flowering period.

Spinosad Products

Spinosad solutions are safe for children, animals, and plants. Since spinosad products are fully organic, you can use them directly on your crops to get rid of pests and other insects. Moreover, such solutions focus on the areas under your plant’s leaves, leaving no stone unturned. Despite being safe for your plant and its surroundings, spinosad products are relentless in fighting cannabis pests, so say goodbye to whiteflies, grasshoppers, leaf miners, spider mites, or aphids.

Neem Oil Extract for Cannabis Pests

Neem oil extract is a safe product as long as you keep the use in moderation. I mean, it keeps your plant healthy and free of pests, but when you go overboard with the oil, it can impact your harvest. That being said, if you use the extract right before harvesting your buds, remember to rinse them afterward. Neem oil extract succeeds in fighting fungus gnats, scales, spider mites, whiteflies, scales, and aphids.

For additional resources on growing marijuana, please check out the cannabis books we reviewed in our article, The Top 7 Books on Cannabis.

What’s your experience with fighting cannabis pests? How do you keep your precious plants healthy and clean? Do you learn from other growers or are there any particular resources you’d recommend?

I’m leaving the stage to you!

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