Caterpillars are one of the most destructive pests that marijuana growers struggle with on a daily basis. These small, destructive pests are able to devour a small area filled with marijuana plants in a matter of days. When your harvest is at stake, it is important to learn how to get rid of caterpillars as quickly and easily as possible.

While experienced marijuana growers may argue that it is not difficult to eliminate caterpillars, and other pests, in your grow area; amateur growers may still need some information on how best to get rid of pests effectively.

Read on to learn simple and effective ways of keeping caterpillars off of your cannabis plants. Let us look at what a caterpillar is, and learn how to handle this hungry pest that will destroy your weed farm.

What Is a Caterpillar?

Caterpillars are insects in their larval stage. They are not yet mature. You can find caterpillars in butterfly and moth species and scientists believe you can get over 175,000 different species across the world.
In its larval stage, a caterpillar is perhaps the most devastating creature in the butterfly and moth family. Although small and not yet mature, a caterpillar can measure anywhere between 1mm and 15 centimeters.
A majority of the caterpillars in the world today are herbivorous, meaning they purely feed on greens or herbs. However, you can find a minority that is either carnivorous or cannibalistic.


Considering their specific anatomy, it is easy to tell the difference between caterpillars and their larval counterparts from other species. Some of the features that distinguish caterpillars are:

  • 12 simple eyes (stemmata).
  • 5 pairs of legs at maximum.
  • They have V or Y-shaped lines on the front of the body.
  • They have crochets and limbs that make it easy for caterpillars to climb on their prey without difficulty.

It is not easy to spot a caterpillar on your weed garden, but you will definitely notice a big change the moment these insects invade your crops. They are known to cause massive destruction within a few days and, unless you do something, can quickly destroy all of your plants.
Luckily, you are not without help. It is easier now to learn ways to keep caterpillars off your weed plants. However, even before you learn how to prevent caterpillars on weed plants, you must be able to recognize if caterpillars have invaded your plants.

How to Tell Caterpillars Have Infested Your Cannabis

A caterpillar invasion of your cannabis can occur in several ways, it is important to learn how to recognize them. To recognize them you must look for signs that are small and subtle to big and noticeable. It can be some leaves have been chewed on, or it can be as bad as the complete devastation of your leaves, buds, and branches. However, the pests may show up, if left undealt with, they can eventually destroy your entire marijuana grow.
There are a few early signs to keep an eye out for. Some of the noticeable features of caterpillar invasion include:

Chewed leaves and flowers

The first thing you are likely to see if there is a caterpillar invasion is holes on leaves. As mentioned, caterpillars are herbivorous and they devour any green matter fast. Leaves are the first signs. Apart from the leaves, caterpillars will burrow deep inside the marijuana buds. In fact, caterpillars target fresh buds and the result is a wilting bud and crop in general.

Marijuana plants

Leaf yellowing

After a few days of caterpillar invasion, your plants will start to show yellow leaves. In most cases, this happens after some damage has been done to the stem and or the roots.

Irregular holes

Caterpillars have no manners at all. They chomp your weed leaves with no regular pattern at all. The holes may be tiny, some measuring a few millimeters while others measuring up to a few centimeters, without following any specific pattern.

Caterpillar leaf

Stem damage

The worst havoc is caused when the caterpillars eat the stems. These insects start by digging holes into the stem to devour the materials in the marijuana stalk. If left untreated, the stalk will fall in no time, and that would be the end to that marijuana stalk.

Ingenious Ways On How to Get Rid of Caterpillars On Marijuana Plants

Once you’ve noticed the infestation of caterpillars in your marijuana, you need to act fast lest they devastate the crop. What can you do to get rid of these insects from your cannabis? This part will explore four proven ways on how to get rid of caterpillars on weed plants.

1. Remove Them Physically

Are you wondering if it is possible to remove caterpillars from your farm physically? While it would be difficult, if not impossible, to do so on large parcels of land, those growing on smaller plots may be able to remove the caterpillars by hand. Once you spot the caterpillar, you simply remove it and kill it. This method requires a lot of time and observance. You will need to keep a constant eye on your crops.

2. Use Bacterial Sprays

Bacterial sprays that contain certain pesticides are very effective in annihilating caterpillars. If you choose this as your preferred method, you need to find a spray pump and use it as directed on the pesticide label. Make sure you find a spray that will not harm humans. Also, keep in mind that these may kill beneficial insects also. You should not apply pesticides when you are nearing harvest time.

3. Depend On Praying Mantises

Praying mantises may appear to be pests themselves, but they are actually very good at eliminating caterpillars. These creatures wait patiently for anything that may invade your crops and the moment they spot caterpillars, praying mantises turn these devastating caterpillars into their next meal.


4. Count On Parasitic Wasps

Another insect that will work at controlling caterpillars on your behalf is parasitic wasps. This army of parasitic wasps knows what they want in caterpillars – they kill caterpillars and some use the bodies of caterpillars to lay and hatch their eggs. If you can get the ecosystem to do your work for you, then that makes your job so much easier.


Bottom Line

You should not be overly anxious when caterpillars invade your cannabis. If you are able to pick them manually, do it. But if you have a huge parcel of land where you’ve put your cannabis, then apply other methods, especially the use of bacterial sprays. Otherwise, for small portions, wasps and praying mantises can do the job for you and save you a lot of time and resources. The best way to take care of a caterpillar invasion on your cannabis is to act quickly.