How to Deal With Stink Bugs on Cannabis Plants?

Stink bugs — they don’t call them that for nothing — these little pests release a foul odor when they are threatened or squished. But that’s not what should worry you about them. If you’re growing cannabis, they can and will damage your plant. Like most other pests, they will eventually reduce the quality of your harvests, so it's best to prevent them. 

But before you think about stomping them out, think again. There are better ways to deal with them without stinking up your grow room. As the name implies, they cause quite a stink! And, you really don't want that terrible smell in your grown room! Fortunately, with the right methods, you can get rid of them easily. In this article, learn about how to get rid of and prevent stink bugs in your cannabis grow room. 

What are Stink Bugs?

Stink bugs are notorious for letting off a foul odor when they feel threatened — talk about a flight or fart response — but the real trouble comes from the damage they can do to your precious cannabis plants. 

Often, you may not even realize these pesky bugs are around until they’ve already caused significant harm. They are especially problematic for cannabis as they feed on the leaves and buds, sucking off vital nutrients. This is why it’s easy to confuse a stink bug infestation with nutrient deficiencies. 

Sometimes, they can also target cannabis seedlings, which are at a higher risk because they are already fragile. They don’t need an insect sucking off what little nutrients they have. 

Apart from that, you should not fear them. They are harmless to humans, and some of your friends may even find them cute. But don’t let their cuteness fool you, though; you need to get rid of them if you want to save your cannabis plant. 

Identifying Stink Bugs 

Before you start your hunt for these bugs on your cannabis plant, it’s important to know what you’re looking for. Thankfully, stink bugs are relatively easy to identify if you know where to look. Otherwise, you may not find them so easily. 

These insects can grow up to 1.7 cm in size and are characterized by their wide, hard, shield-like shells. Most stink bugs are brown with various markings, but you may also encounter bright green ones. You’ll find them walking around on your plant and, sometimes, a nasty odor near your plant. 

Aside from being a nuisance, stink bugs are prolific breeders. They lay clusters of white eggs that quickly hatch into larvae, which then mature into adult stink bugs. If left unchecked, their numbers can multiply quickly, making it even more difficult to protect your plant. So, look for clusters of white eggs, too.

Symptoms of a Stink Bug Infestation in Cannabis Plants

Stink bugs aren't as terrible as other pests like spider mites or aphids that can totally ruin cannabis. Still, it's better to make sure they don't disturb your plants. Thus, recognizing them early might help you keep your plants happy. 

1. Live Stinkbugs

This one’s obvious: the most common indicator of a stink bug infestation is seeing the bugs themselves on your plants. These critters which look like they are carrying a shield are usually found in clusters on the stems, leaves, and near buds (especially during late spring/summer). 

2. Yellowing or Browning Spots on Leaves

Stink bugs pierce the soft tissues of the plant with mouthparts that are as sharp as needles and suck the nutrition. As a result, you'll notice light yellow, brown, or even white marks on the leaves. These spots can enlarge over time, which may result in the leaves turning yellow and making your plant more susceptible to disease.

3. Wilting or Drooping Leaves

Stink bugs can prevent the plants from taking in much-needed food and water when they suck the sap. Thus, the leaves start wilting or drooping even if you're watering correctly. In more severe cases, the affected leaves might fall off as the plants become too weak. 

4. Deformed Buds and Flowers

Although stink buds typically love the leaves, they can target the buds as well. As a result, the buds may look abnormal and deformed. Sometimes, the buds may fall off entirely before the plant is due for harvest. 

5. Foul Odor

As their name suggests, stink bugs smell bad when they are disturbed or squished. This odor can linger on the plant and the grow room, leaving little doubt that there are stink bugs around. 

6. Reduced Potency 

Cannabis buds depend on their sap, which is full of nutrients, to produce trichomes that contain cannabinoids. But since stink bugs feed on this sap, the production of these cannabinoids is disrupted and you may end up with less potent buds. 

How to Remove Stink Bugs from Your Cannabis Plant?

While it may not always be easy to spot stink bugs on your plant, getting rid of them is relatively straightforward. Here are some awesome ways you can get rid of stink bugs on your cannabis plant. 

• Clean Your Grow Room 

When you spot a stink bug on your cannabis plant, it’s time to bring out your vacuum cleaner and broom to give your grow room a thorough clean down. Start by removing all debris and dead leaves from around your plant. This will clear out any bugs hiding in your grow room and prevent them from coming back. More on this later. 

• Pick Them Off One-by-One 

Stink bugs are notorious for releasing a nasty odor when they feel threatened or crushed. So, don’t crush them or swat them like you would a fly. You’ll regret it. Instead, simply pick them off by hand — they are completely harmless to you. Protip: you can always call your friend who finds them cute! 

Carefully pick the bugs and drop them in a bucket of soap water. This method is effective and prevents the bugs from releasing their stinky defense mechanism. Afterward, be sure to dispose of any dead stink bugs away from your plants to avoid attracting other pests. 

If you don’t want to handle them, you can place the bucket of water under them and flick them off. They tend to drop to the ground when they are surprised, so you can use that to your advantage. 

• Check for White Eggs

It’s not enough to just remove the bugs — you also need to check for any eggs they may have laid on your cannabis plant. Look for clusters of white eggs on and under the leaves. If you find any, remove the affected leaves immediately to prevent them from hatching and creating a bigger problem. 

• Wash Your Plant 

If the infestation is severe, you can take your plant outdoors and gently wash it with a hose. Make sure the water pressure is low to avoid damaging your plant. Before hosing, you can also shake the plant to dislodge any bugs, then carefully flush away any remaining eggs and buds. 

• Use Neem Oil 

If the above methods don’t fully resolve the issue, use neem oil. Unlike harsh chemical pesticides, neem oil is completely safe for cannabis and works as a natural preventative measure against these bugs. 

However, neem oil is only effective against eggs and larvae — you’ll still need to remove adult bugs with other methods. 

When using neem oil, it’s important to emulsify it properly to avoid harming your plant. Many growers make the mistake of mixing neem oil with water and spraying it directly. Instead, mix neem oil with a silica solution or soapy water so it mixes well with water. 

Silica is a great emulsifier for this as it can also provide additional nutrients for your cannabis, strengthening their cell walls and promoting better bud growth. 

To make a neem oil solution, mix an ounce of water with 4-5 grams of silica, then add a tablespoon of neem oil to the mixture. Use warm water to make the emulsification easier. Fill your spray bottle with the solution, shake it well, and spray it on the leaves. 

Remember not to spray neem oil on your cannabis when it is flowering. It has a strong scent that can damage the buds’ flavor and aroma profiles. Also, it’s best to spray it just before the lights go off or at sunset to prevent nutrient burns. 

• Chemical Treatments

If you have a stink bug infestation that organic or preventative measures can't control, chemical treatments may become necessary. But you need to be careful while choosing such chemical insecticides as they may be harmful to you and the environment. 

Moreover, not all insecticides are great for cannabis plants as they can damage the plant or leave a harmful residue that could make your finished product unsafe to consume. If you have to use chemical treatments, use the ones that are safe to be used for cannabis. Get the manufacturer's instructions and read them carefully before applying any insecticide. Stick to the recommendations and do not exceed them even if you think they aren't working as your safety is at stake too.

Apply chemical insecticides during the early morning and late evening when stink bugs are most active (avoid high heat from peak sun that may cause rapid evaporation of applied insecticide). Also, try to use insecticides only during the vegetative stage as applying these chemicals during the flowering stage may change the taste of the buds. Agreed, you can't predict when pests are likely to attack and if they do infest the plants during the flowering stage, it's best to use organic measures to stay on the safer side.

Here are a few insecticides that are deemed safe for cannabis:

Pyrethrin-based Insecticides

You can use pyrethrins (insecticides made using chrysanthemum flowers) in controlling stink bugs as they are a broad-spectrum insecticide. Most pyrethrins are considered to be low in toxicity and are pretty safe for humans, pets, etc. Many cultivators use pyrethrins to control a variety of pests attacking cannabis plants as they attack the pests’ nervous system, causing paralysis and death.

Insecticidal Soaps

Insecticidal soaps can be successful against stink bugs as they erode the protective outer coating of an insect which eliminates their ability to control moisture. They are often used to provide a safe chemical alternative for cannabis plants, especially in the early stages of infestation. It is usually safe to use them both indoors and outdoors.

Spinosad

This is a microbial insecticide derived from soil bacteria, making it an eco-friendly alternative to control pests. Like pyrethrins, it attacks the nervous system of stink bugs. You can use it on cannabis safely as it breaks down pretty quickly, reducing the likelihood of toxicity. 

Here are a few things you should keep in mind if you’re using strong chemical insecticides or pesticides:

• Apply in a Well-Ventilated Place

When using indoor insecticides, make sure your room is well-ventilated to prevent toxic fumes from accumulating. Outdoors, do not spray on a windy day as the pesticide can drift to other plants or beneficial insects.

• Protect Beneficial Insects

Most chemical insecticides also kill beneficial insects like ladybugs, bees, and predatory wasps that keep other pests in check. To prevent this, spray on affected areas instead of dousing the entire plant. Do not spray chemicals when pollinators are present so that you don't harm them. 

• Wear Protective Gear

Use gloves, goggles, and a mask to protect yourself from harmful dosages of chemicals when handling or applying insecticides. After applying, make sure to wash your hands well.

• Wait for Harvest Intervals

Don't forget the minimum pre-harvest interval (PHI) that is typically printed on your insecticide label. It tells you how long to wait from the last application until harvest. This is to make sure that the chemicals have broken down effectively. 

• Regular Monitoring

Do not forget to inspect your plant regularly after applying chemical pesticides as you may need to re-apply if the pests are still lingering in the plant. However, try not to use more chemicals than necessary since too much will result in plant stress/toxicity.

How to Prevent Stink Bugs on Cannabis?

When it comes to growing cannabis, prevention is always better than cure, especially with pests like stink bugs. After you’ve successfully removed them from your plant, it’s time to take some steps to prevent them from returning. 

Stink bugs are more likely to invade your grow room when the weather turns cold, as they seek warmth. Your controlled grow room, with its ideal temperature and humidity, becomes an inviting haven for these pests. To keep stink bugs out for good, follow these preventive measures:

1. Seal Entry Points 

Start by thoroughly inspecting your grow room for any potential entry points such as holes, cracks, or gaps around the windows, ventilation, doors walls, etc. These bugs can easily sneak through them as they are small, so you need to seal them up using sealants or chalking. Close windows and doors properly when they are not in use. 

If you want to expose your plant to fresh air, use a fine mesh net screen on your windows to act as a barrier against these pests while still allowing airflow and light into your growing space. 

2. Use Diatomaceous Earth 

Another effective method for keeping stink bugs at bay is spreading diatomaceous earth around entry points and areas where stink bugs are prevalent. Diatomaceous Earth is a fine powdery material produced from crushed fossilized algae and kills stink bugs (and most other soft-bodied insects). It can destroy the exoskeleton of stink bugs, leading them to dehydrate and die.

Lightly dust food-grade diatomaceous earth along entry points such as doorways, windowsills, and even cracks in the walls. When using diatomaceous earth indoors, be sure to use food-grade quality to ensure safety around humans and pets. After a few days, vacuum up the diatomaceous earth along with any dead stink bugs. Reapply as needed, especially after a wash or strong airflow.

However, one problem with diatomaceous earth is that it won’t work if the soil is wet, so you may not be able to get rid of pests in the soil. In such cases, wait for the soil to dry and apply it or use other methods. 

3. Cover Outdoor Plants

If you’re growing cannabis outdoors, covering your plants can help prevent stink bug infestations. Use protective coverings like insect netting or row covers while still allowing adequate sunlight and airflow through. These coverings act as barriers to keep stink bugs and other pests from attaching themselves to your plants. Remember to anchor protective coverings to the ground if you’re using them. This way, the bugs won’t have openings to crawl in. Check the netting often to ensure it is not ripped or weakened and adjust as needed as your plants grow bigger, so there are no gaps while still allowing light through.

4. Inspect Your Plant Often 

Even with all these preventive measures in place, regular inspection of your cannabis plants is essential. Check your plants frequently for any signs of stink bug activity, such as eggs, larvae, or the bugs themselves. Early detection can help you address the problem before it becomes a full-blown infestation.

5. Maintain a Clean Grow Room

Keep the grow room clean and in good condition since stink bugs, like most other pests, are drawn to areas offering shelter and food sources. They serve as the best breeding grounds for them. Thus, a clean and organized grow room is less likely to offer pests a chance to establish themselves. 

For example, stink bugs love to hide in debris, dead leaves, and old plant material on the floor or around your grow site. To prevent this, frequently clean the floor and area around plant pots by sweeping up any dead leaves/ stems or anything else that might fall off your cannabis plants. Also, remove dead foliage or fading leaves from your plants promptly to prevent build-up. Use a vacuum or broom to sweep up debris once per week, so the space remains neat.

Next, you need to sanitize your tools. Any tools including scissors, trimmers, or even plant pots can carry pests (or eggs) from one place to another that you’ve used before, so it’s a good idea to sterilize and clean them. Simply dip all your tools in rubbing alcohol or a mild bleach solution to ensure that any insect eggs and larvae are killed.

Remember, stink bugs and other pests will be drawn to high-humidity areas because they thrive in damp, warm environments. This is also a perfect condition for mold to grow, which in turn attracts pests. To avoid this, use dehumidifiers or ventilation systems to regulate the humidity levels within your grow room to create ideal conditions without attracting pests.

Do not water your plants too much as you may end up overwatering the plants and raising humidity as well. 

6. Place Traps In And Around Your Grow Room

You can also use traps to keep stink bugs out of your grow room. This way you'll prevent the problem rather than having to deal with it later. One good way you can deal with this is by using sticky traps in your indoor garden or placing them near the entry points to catch any bug that tries entering from outside. You can also put out light-based traps that lure stink bugs to them in the evening. In essence, place these traps just outside the grow room so they are caught before they have a chance to make it inside. 

7. Control Moisture and Temperature

Many pests including stink bugs are attracted to warm, humid conditions and this can make your cannabis grow room a hot spot for these critters if you don't control the environment accordingly. Correct temperatures and humidity levels will discourage pests such as stink bugs and contribute to the overall health of your plants. Here are a few things you should keep in mind: 

• Best Temperatures for Optimal Growth and Pest Deterrence

When the temperature outside drops, stink bugs are more likely to make your home their residence, especially during the frigid months of winter and fall. In the winter, they can head indoors to find sanctuary in warmer conditions as it's challenging to look for a mate and lay eggs outdoors. During these times, temperature and humidity control needs to be your top priority as you can deter these pests from living with your plants by maintaining the right environmental conditions. 

Therefore, lower the temperatures slightly if you're growing cannabis during the winter. But don't overdo it as you may end up killing your plants along with the stink bugs! Basically, just maintain a normal range and hope that they don't find your grow room interesting.

Ideal Temperature Range: The ideal temperature range for cannabis plants is usually 70-85°F (21-29°C) during the day and about 58-70°F (14–21°C) at night. Maintaining this range helps you grow healthy plants as it's unfavorable for stink bugs. 

This means that you should prevent the room from getting too hot at all costs. Hot temperatures attract all sorts of pests, and stink bugs are no exception. In addition, extreme temperatures exert a lot of stress on plants, causing them to grow slowly and reducing yield as well. 

Apart from the temperature, stink bugs prefer high humidity as well. To prevent this, you should maintain a healthy range of about 50-70% RH in the grow room. During the flowering stage, the plants prefer about 40-50% and although it might be tough to reduce the humidity too much, this range will keep your plants safe and healthy. 

If you live in a region that has high humidity, consider investing in a good dehumidifier. In addition, get a good hygrometer to keep the temperature and humidity in check. Don't forget to maintain your tools well so they work for a long time. 

Alternatively, you can also increase the ventilation in the grow room to reduce heat. Not only does it regulate the temperatures, but will also help you control the humidity and prevent the pests from invading the plants. 

You don't have to invest in any sophisticated equipment to increase the airflow. Instead, get some good oscillating fans to avoid hot spots that stink bugs love. 

Keep in mind that you'll have to check your air filters or HVAC systems frequently and clean them if you're using them. Make sure the pests don't enter through these filters as dirty filters can trap moisture and provide an entry to stink bugs. 

By following these steps, you can keep your grow room stink-bug-free (and stink-free) while ensuring your plant remains healthy and thriving. Prevention is key to avoiding the stress and potential damage that pests like stink bugs can cause, so stay vigilant and proactive in your efforts.

Summary: How to Deal With Stink Bugs on Cannabis Plants?

Getting rid of stink bugs may seem like a daunting task, but with the right methods, you can protect your cannabis plants from these smelly invaders. By understanding how stink bugs operate and taking proactive measures, you can keep them at bay and ensure your grow room remains a sanctuary for your plants. 

Remember, prevention is your best defense—seal up entry points, secure your windows, and inspect your plants regularly. With a little vigilance, you can enjoy a healthy, pest-free cannabis harvest without any unwelcome surprises.

But if they still make their way into your cannabis room, you can either pick them off one by one or hose down your plant. Either way, don’t forget to check for their eggs under the leaves!