Common Pests on Marijuana

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When it comes to marijuana, you want to safeguard it as much as possible. Whether you’re using it for medicine, recreational or a large scale legal operation, one thing you know is it can take a long time to grow cannabis. Although they can grow like crazy, it generally takes 8-12 weeks to grow, regardless if you’re growing cannabis indoors or outdoors. If this is going to be your only crop for the next 6 months, you want to make sure none of them will get ruined or you will lose a whole lot of money. If it’s just for medicinal reasons and you’re growing a specific strain, you will find yourself on weedmaps trying to find the nearest dispensary.

Growing cannabis is not the easiest task. It’s time consuming and everything needs to be done just right for it to be as potent as possible. Making sure you don’t cut corners and you’re dotting your i’s, crossing your t’s, you will be alright. However, after doing all that, there are still external forces that can mess up your crop. Bugs, mites and small insects that love to nibble on your plants.

What are Marijuana Pests?

Marijuana pests are common insects that you will see on your plants. Although some small insects and animals are ok to be around because they kill the harmful insects, others are not good. Spiders might make a web and kill the mite that is out to get your plants buds but some smaller unnoticeable insects are harmful. They will eat the plants and leave bacteria that kills the plant.

One of the problems with pests is they often require pesticides or insecticides to kill the pests. With cannabis, it’s a problem because these are dry herbs you end up smoking. Whether you pack it in a water pipe or turn it into wax and put it into your dab pen.

Common Pests

Here are the most common pests that will eat and harm your marijuana plants. You want to continuously watch out for them. Whether they’re underneath the plant or in the soil, use a well lit room to look out.There are multiple ways to make sure these pests don’t keep coming back.


Aphids which are also known as green fly or black fly are tiny soft-bodied insects. Unlike the name, it can appear to be black or green but also white, yellow, brown or red. It all depends on which stage of their life they’re in. If they are black or really dark and round, they are towards the later stage in their life. White and smaller aphids are younger. However, be careful not to mistake these with thrips that are white bugs that look like tiny fat worms.

Leaf Miners

Sometimes insects have names that don’t match their characteristics but this one does exactly as it’s called. Leaf miners drill down on the plant like a miner. They do this and tap away the essential nutrients the plant carries. If you notice brown or yellow streaks with small tiny holes in them, you have yourself a case of this. Check underneath the leaves and see if you see any larvae of leaf miners. It’s not easy to get rid of these little ones.

Spider Mites

Usually, spiders are a great arachnid to have around as they kill other insects but this one isn’t a spider like the name says. It is actually a mite which are very harmful to your cannabis plants. You will notice little yellow or white specks on the leaf. These are bite marks that they leave. A spider mite is generally on the bottom of the leaf and is very tiny. They are black colored and will be seen walking around.


Caterpillars are cute fuzzy little creatures that are harmless and most of us even read about “The Very Hungry Caterpillar” when we were a kid. However, caterpillars are a great threat to your plant. The first thing you see when they’re around are chunks of leaves missing or eaten. You will often see clumps of black or brown dirty, which is caterpillar poop.


Mealybugs are one of the weirdest looking insects to love your plants and they’re around when the weather gets warmer. They produce a sticky sweet sap like substance called honeydew.These can be very annoying and come in as a unit.


Whiteflies are very similar to spider mites. They hang out underneath the leaves and take nutrients away from the plant. They can be spotted by just looking underneath the leaves and if they aren’t taken care of. There will be a very big infestation.


Thirps can definitely damage and make your plants look ugly. Thirps are very small but quick insects that leave silver or bronze spots on the leaves.If you don’t treat it quick enough, these spots will eventually dehydrate and dry out your plant. Some thirps are dark and others are yellow or transparent.

Fungus Gnats

You may have seen these little pests, the fungus gnat is a very tiny fly that usually flies around the soil, especially with indoor growing. Their larvae grows in wet top soil so all this makes it a perfect environment for them to thrive. The best way to make sure you don’t keep encountering these pests is to simply let the top soil get a bit dry. This can kill the larvae.