“Help! I’m seeing little black bugs on my buds!” You have no idea how many times we’ve heard our readers say this. And with good reason. Even the pros have a bug problem from time to time. The difference is, though, that the pros have learned to recognize and deal with the little black bugs (or any pest, for that matter) preemptively. Now, so will you.
Growing cannabis, no matter if it’s indoors or outdoors, comes with its fair share of challenges, and pests are often at the top of that list. Just like any other plant, your cannabis can fall victim to tiny critters that love munching on tender new growth, green leaves, and buds. From aphids to spider mites, these cannabis pests can cause big problems if left unchecked.
This guide will help you identify the most common pests, show you how to prevent infestations, and give you tips on eco-friendly ways to manage these pests without harsh chemicals.
- Identifying the Most Common Cannabis Pests
- Top 10 Most Common Pests on Cannabis Plants
- 1. Aphids on the Underside of Your Cannabis Plant’s Leaves
- 2. Leaf Miners on Your Cannabis Plant’s Leaves
- 3. Caterpillars on Your Cannabis Plant, Stems and Buds
- 4. Spider Mites on Your Cannabis Plant’s Leaves (and Flowers)
- 5. Thrips on Your Cannabis Plant Leaves
- 6. Whiteflies on the Underside of Your Cannabis Plant’s Leaves
- 7. Mealybugs on the Stems and Leaves of Your Cannabis Plant
- 8. Fungus Gnats on and in the Soil of Your Cannabis Plant
- 9. Nematodes in the Soil of Your Cannabis Plant
- 10. Slugs & Snails on and in the Soil of Your Cannabis Plant
- Pest Prevention Strategies for Cannabis
- Quick Pest Control Tools for Beginners
Identifying the Most Common Cannabis Pests
Before we talk about how to prevent or manage pests, the first step is being able to recognize them. It’s easy to miss the early signs if you’re not sure what you’re looking for (or if you’re not looking at all). Let’s start with a quick overview of why pest control is essential.
Why Is Pest Control So Important for Cannabis?
Cannabis plants are particularly attractive to a range of pests because they provide a great source of nutrients. Whether it’s the sweet-smelling buds or the sap inside the leaves, pests are drawn to cannabis and can cause serious harm if left untreated. This is especially important for home growers since an infestation can spread quickly and ruin your entire crop.
Without the right controls in place, cannabis pests can lead to:
- Stunted plant growth
- Reduced yields of buds
- Damaged or unusable cannabis
By identifying the signs early on, you can tackle the problem before it gets out of control.
Top 10 Most Common Pests on Cannabis Plants
1. Aphids on the Underside of Your Cannabis Plant’s Leaves
Aphids are small, soft-bodied insects that feed on the sap of your cannabis plants. They’re sneaky—they often hide on the undersides of leaves, making them tough to spot at first. Aphids reproduce quickly, which means a small problem can turn into a full-blown infestation fast.
Symptoms:
- Curled or twisted leaves
- Yellowing of leaves
- Sticky “honeydew” residue, which can lead to mold
Prevention & Treatment:
- Keep your cannabis plants healthy by avoiding over-fertilizing.
- Use yellow sticky traps to monitor for aphids.
- Remove damaged leaves and use neem oil or introduce ladybugs to control the population.
2. Leaf Miners on Your Cannabis Plant’s Leaves
Leaf miners are larvae that burrow through your cannabis leaves, creating visible tunnels. They don’t kill the plant, but they reduce the cannabis plant’s ability to photosynthesize, which can affect your yields.
Symptoms:
- Thin, white lines or tunnels on leaves
- Leaf drop
Prevention & Treatment:
- Remove affected leaves immediately.
- Encourage natural predators like parasitic wasps.
- Keep the growing area clean and free of debris to minimize infestations.
3. Caterpillars on Your Cannabis Plant, Stems and Buds
Caterpillars are one of the most destructive cannabis pests for outdoor cannabis growers. These little creatures often bore into the stems, chewing their way out again through buds and seriously damaging the plant.
Symptoms:
- Holes in leaves
- Holes in stems with “sawdust”-looking debris
- Visible droppings on leaves
- Damaged, hollow, and sometimes even moldy buds
Prevention & Treatment:
- Handpick caterpillars off your cannabis plants.
- Use neem oil or organic insecticides designed for cannabis.
- Encourage predatory insects like parasitic wasps or introduce beneficial nematodes to your soil.
4. Spider Mites on Your Cannabis Plant’s Leaves (and Flowers)
Spider mites are tiny but mighty pests that reproduce rapidly and can decimate a crop in no time. They’re easy to miss because of their small size, but these little black bugs on your buds often leave behind webs, which is a clear sign of infestation. (Actually, not all spider mites are black. They come in many colors, depending on age and species, including green, orange, red, and yellow)
Symptoms:
- Yellow or bronze-colored leaves
- Fine webbing on leaves or buds
- Speckling on leaves
Prevention & Treatment:
- Keep your cannabis environment humid—spider mites thrive in dry conditions.
- Rinse your plants with a hose or mist them regularly to disrupt spider mites.
- Use predatory mites or neem oil to control spider mite populations.
5. Thrips on Your Cannabis Plant Leaves
Thrips are small, slender insects that feed on cannabis leaves, causing damage to the plant’s cells. They can be difficult to spot, but their feeding habits leave behind visible signs.
Symptoms:
- Silver streaks on leaves
- Tiny black dots (their droppings)
- Deformed leaves
Prevention & Treatment:
- Regularly clean your grow area, as thrips thrive in dirty environments.
- Use yellow sticky traps to catch adults.
- Introduce beneficial insects like predatory mites or use neem oil.
6. Whiteflies on the Underside of Your Cannabis Plant’s Leaves
Whiteflies are small, white, moth-like insects that suck sap from cannabis plants. They usually hang out on the underside of the leaves, just like aphids, and they can reproduce quickly, leading to a large infestation.
Symptoms:
- Wilting or yellowing leaves
- Sticky residue on leaves (honeydew)
- Tiny white flies when you disturb the plant
Prevention & Treatment:
- Use yellow sticky traps to capture adult whiteflies.
- Spray plants with a mild soap solution or neem oil.
- Encourage natural predators like ladybugs or parasitic wasps.
7. Mealybugs on the Stems and Leaves of Your Cannabis Plant
Mealybugs are small, white, cotton-like insects that cluster in the nooks of your cannabis plant. These cannabis pests suck sap from the plant, causing wilting and sometimes stunted growth.
Symptoms:
- White, fluffy patches on leaves or stems
- Yellowing or curled leaves
- Sticky honeydew and possible mold growth
Prevention & Treatment:
- Hand-remove the bugs and their egg sacs.
- Use neem oil or insecticidal soap.
- Encourage natural predators like ladybugs or lacewings.
8. Fungus Gnats on and in the Soil of Your Cannabis Plant
Fungus gnats are small, mosquito-like insects that lay their eggs in the soil. Their larvae feed on roots, which can seriously damage young cannabis plants.
Symptoms:
- Slow plant growth
- Yellowing leaves
- Little black bugs on your buds or hovering around the soil
Prevention & Treatment:
- Allow the soil to dry out between waterings to prevent egg laying.
- Use yellow sticky traps to monitor adult gnats.
- Apply a hydrogen peroxide and water drench (mix 1 part 3% H2O2 with 4 parts water) to kill larvae.
9. Nematodes in the Soil of Your Cannabis Plant
Some nematodes are beneficial, but others can be harmful to your cannabis plants. Harmful nematodes attack the roots, leading to wilting and poor plant growth.
Symptoms:
- Stunted growth
- Wilting despite watering
- Poor root development
Prevention & Treatment:
- Use sterilized soil and avoid using garden soil in your containers.
- Apply neem oil or beneficial nematodes to control harmful species.
- Rotate your crops if growing outdoors to break the pest cycle.
10. Slugs & Snails on and in the Soil of Your Cannabis Plant
These pests are more common for outdoor cannabis growers. Slugs and snails can chew through leaves and stems, leaving large holes in your plant or taking out a seedling before it gets a chance to grow.
Symptoms:
- Large, irregular holes in leaves
- Slime trails on the soil or plant
- Chewed leaves or stems
Prevention & Treatment:
- Remove dead leaves and loose mulch from the base of plants (this is where they hide)
- Set up copper barriers or beer traps to deter them.
- Remove slugs and snails by hand.
- Encourage natural predators like frogs, toads, or birds.
Pest Prevention Strategies for Cannabis
Now that you’ve got the lowdown on the most common pests, let’s talk prevention. The best way to manage cannabis pests is to stop them from getting to your plants in the first place. Here are some strategies I’ve picked up over the years that work like a charm:
1. Maintain a Clean Growing Environment
Keeping your grow area clean is the most effective way to prevent pests. Pests love messy, damp environments where they can hide and breed.
- Indoors: Wipe down surfaces, avoid overwatering, and always clean your tools before using them.
- Outdoors: Keep the area around your plants free from weeds, dead leaves, and debris that might attract or host those pesky pests.
2. Use Physical Barriers
If you’re growing outdoors, using barriers can keep some pests away. For instance, copper tape is great for deterring slugs and snails, while netting can help keep larger cannabis pest animals like deer away.
3. Rotate Your Crops
Pests often overwinter in the soil, which means they can reappear if you keep planting in the same spot. Rotating your cannabis crops each season can help break their life cycles.
4. Monitor Regularly
Use tools like yellow sticky traps to monitor flying insects. Check your plants daily, especially the undersides of leaves where cannabis pests like to hide. A little early detection can go a long way!
Quick Pest Control Tools for Beginners
Yellow sticky traps for monitoring flying pests
Hand lens (loupe) or magnifying glass for spotting tiny insects
Neem oil for natural pest control
Insecticidal soap for soft-bodied pests
Hydrogen peroxide to treat soil pests
Copper tape or barriers to deter slugs and snails
Manual sprayer for applying treatments
Beneficial insects like ladybugs or predatory mites
Pruning shears for removing infested plant parts
Sterilized potting mix as a backup for contaminated soil
There you have it, folks! Now, you’re armed with the knowledge you need to keep your cannabis plants healthy, happy, and pest-free. Keep an eye out for early signs of little black bugs on my buds, stay on top of prevention, and use natural solutions whenever possible. Your plants (and your future harvest) will thank you!
I am an indoor grower and I think zi have a bug problem. The plant looks good except some yellowing leaves. I didn’t think much of it because my plant is flowering and I expect some yellowing. I have a really strong loop, I looked at the leave and could see little round holes but no bugs HELP
I have little white bugs I have a lot in my soil but have not noticed them on the leaves what could this be?
Its harvest time and noticed i have afvids bugs on my plants thick on stems and leaves and appears dead ones all over the leaves and buds how is this going to affect.my finished product ?? Will they die and evacuate tge plant once harvested ?
I pulled one bud from the very top of one plant as it has turned dark brown overnight. What would cause this? the other buds on the same plants and the ones next to it don’t show anything. No bugs that we could see even with a magnifying glass.
Is tempo ok for cannabis
Hey I need help. Theres this bug that I HAVE NOO IDEA WHAT IT IS. I seen it before, but I never bother to look it up. Until now. And I cant ligit find anything about it. Can you guys help me out?
hari, Same for you. We cannot guess what pests are flying around.. We need pictures of your flying friends.
I Suggest You Go Here: Support.Ilovegrowingmarijuana.Com Our Members And Staff Can Take A Look At Your Pictures And Give You Informed Advice.
brett,
I Suggest You Go Here: Support.Ilovegrowingmarijuana.Com Our Members And Staff Can Take A Look At Your Pictures And Give You Informed Advice.
I’ve spotted several small brown flying pests but so far, no discernible damage. What are they and how harmful. Thanks
Hey Hari,
Sounds like you are dealing with Fungus gnats, I’d advise you to check out this article: https://www.ilovegrowingmarijuana.com/growing/marijuana-pests-fungus-gnats/
Good luck!
Stacy
ILGM
hi ! everyone i used garlic & onion powder on my plants plus dawn soap too keep the bugs off it works, but when i used the soap it turn the leafs brown . the plant is still growing an hanging in their.
I have a brown substance forming at the junction of leaf and stem, looks like really fine sawdust couldn’t find anything on it any help would be appreciated 4 wks into flower
Went on vacation and came home to boreworms.ouch!
I appreciate the time and dedication you put into creating this book full of information. This excerpt was exactly the info i was looking for.
A lot of useful information
Your own link to CORNMEAL says you’lol be feeding the ants, not killing them. It’s the insecticide they mix with cornmeal that kills them. Put cornmeal on your ants and you’re feeding them!
I plan to grow in the bush where gusts of wind come from the hills. Autoflowering seeds are the plan, lots of small plants. I’ll be roughly 100 metres from a lake, is that beneficial for frogs?
I’m going to use insecticide.
Caterpillars are really the only problem I’ve encountered.
What stuff should I put near the grow site to deter?
Are bandicoots something to look out for?
How can I setup my grow site to make it more ready for the next grow season?
It’s in the great wide open, but sheltered somewhat.
I’m going to take water to the site in advance for subtlety when I water them..
What else can I do to prepare?
I’m a noob grower btw..
Christopher Cullen,
We would like to see you join our forum at ilgmforum.com where we have members from around your way who can better guide you to success in your region. Your questions are a bit extensive for the blog comment section. tag me @latewood when you get set up in the forum. 🙂
All types of white looking bugs are on my plants how do I get rid of them
Annette Fletcher,
First; I suggest you join us at: ilgmforum.com and our expert staff and many knowledgeable members will be glad to help identify your issues and provide options for eradicating the pests as long as you can show us a couple of pictures of your plants, and the white bugs. 🙂
Bruce,
You could develop root rot due to poorly aerated soil, however, this is just an educated guess.
It would be best for you to join oursupport forum where we can help you figure out what happened , what you may have done differently, and how to be a successful grower. Check out the forum at ilovegrowingmarijuana.com
I start seed in the house then plant outside as soon as possible. All plants are staked. Around 3-4 weeks after replanting the leaves start to drupe. After another week I reached down and pulled out the above ground stalk and found that every bit of root has disappeared. Maybe eaten?? Or is there a disease that would turn the roots to mush and disappear? Thanks
Recently moved to the midwest and have encountered a pest I’ve never seen before. This pest bores a small pinhole into the stalk and creates a swelling at the site. Any thoughts or suggestions are appreciated.
A great way to protect your outside seedlings is to place a clear pop bottle over them (cut off the bottom, take off the labels, and take off the lid). The hole in the top of your bottle lets air and rain in but keeps the birds out. Also acts as a mini greenhouse to get them started.
Great tip, thanks Holly! – I❤️GM
I have found black elliptical type bugs on the stem of the plant (outdoor) what are they and hoe to destroy?
Robert,
There is no real way to answer your question without a picture. I invite you to join our support forum, and you can add a picture to a post so we can identify your pest, or good bug.
Just tag me @latewood when you join and I will try to help you out. Many other members will too! 🙂
Mary,
You don’t mention why you feel these bugs a sapping your stems. I at first though you just had ladybug larvae which are odd looking buggers with orange stripes sometimes. Look up images of Ladybugs before you panic/.
As treatment. Without any pictures or proof that this is the real issue; I usggest you try some insecticidal soap, and join our support forum for a braoder range od support overall. See you there. We need pictures 🙂
I have noticed a flying pest in my garden, slow moving, orange marking. Strangely, there are no bite marks of any kind. The stems have not been as hardy as the first grow, despite still growing large buds. I have deduced that these bugs are Spittlebugs, and they are sapping the stems, literally. How do I eliminate them? I cannot find this pest in anybody’s list for cannabis and need to eliminate them without harm, obviously.
Thanks Roy.
I am not a bussiness and this not a product. I am just trying to find out if I have done something special. I only have one friend that grows so I have very few opinions on this.
If there is an interest in this solution I will gladly work with you to advertise with you. But for now I am just getting opinions and letting growers know it can be done. I almost gave up growing because of all the pests, now it is just fun.
Next I need to find a good way to grow larger buds organically.
I will look at the link you gave me. I am also new to forums.
Thaks Roy
Hey Realdream, the forum would be perfect for you to get feedback. You can sign up in the top right and ask for feedback in the nutrient section 😀
Hey Realdream, you’re welcome to elaborate on the support forum as long as you refrain from directly advertising. Please contact us through the contact form if you ever want to discuss more about advertising.
We’ve been into deep water culture for basic veggies, medicinal and cooking herbs. We ran into all the typical indoor growing pests and have worked now for 2 years to resolve those problems organically. Recently we met a new friend who is very involved in medical MJ hydroponic growing. He had all the usual problems with pests through his grow cycle. He found out what we were working on and gave us a great opportunity to test what we’ve worked with on his crop. We have now done two crops with him and he has had no pest problems and we’ve improved his nutrient uptake and he has had no water change outs with two crops in the same solutions. Only water is added as the system runs low.
We are sharing this with others to get feedback and opinions. We are working with organic manure, organic plant material and organic minerals. Just so everyone is clear, this is not a product on the market, but if it seems it will be we will be glad to do the right thing with the webmaster and pay for advertising or whatever requirements are needed.
For ourselves, we have gotten rid of spider mites, root aphids, leaf aphids, white fly and powdery mildew. The water solutions in the tanks are always fresh and clean smelling, even during harvest and uprooting. As a test our friend tried placing new clones straight back into the old water to see what would happen. He got a second crop with no health issues.
After talking with various growers, we get the same comments; that they don’t believe us and after seeing all the discussions on various forums we understand why that opinion is there. Pests can be a chronic problem. All we do is foliar spray twice a week and add it to the nutrient solution in the water supply tank. Our new friend the grower really likes the results of the crop and likes that it is all organic and disease free.
Sorry for rambling on, but we are very excited. We really would like your comments and responses.
Thanks
Hi, I have a pro, my plants have been eaten in half at the Base just above the soil level, the bugs are about pin head size and white, anybody know what they could be??
Hi THG, have you checked our symptom checkers? And maybe you can upload a picture to our support forum where people can help you spot the bugs.
PatC,
Ladybugs are great if you can keep them around. They eat pests and their eggs; However, they tend to move on if you do not have “bad” insects.
Happy growing 🙂 lw
Are the introduction of lady bugs a good idea for discouraging bad bugs on plants?
[…] source of chemicals applied to marijuana plants. Both soil and hydroponic growers alike face the ravages of pests and mold. Here are some tricks and techniques for dealing with common marijuana diseases and pests […]
[…] sure if mealybugs are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] Be careful with these recipes, however; alcohol can strip your plant of its beneficial resin production. Make sure you follow the home remedy instructions exactly, paying special attention to the quantity you put on the plant, how long it should remain on the plant, what exactly the purpose of it is, and how much you should dilute it. More tips and tricks to control pests in the article Marijuana pest control […]
[…] sure if aphids are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if fungus gnats are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] the article Pest and bug control for more information about outdoor pests, including deer, gophers & moles, snails and many […]
[…] your plants. Not sure if deer are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] if crickets or grasshoppers are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if cutworms are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if birds are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if thrips are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if caterpillars are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
I see nothing about “what to do about Scales…” please help, in dirt, outside, pet 2′ away, taking down 8′ plants, bad with scales, what to do before planting next time ?
I had the same problem and couldn’t find anything on how to get rid of scales and help the plant recover, ended up throwing out three 5′ plants that just started to bud, weird thing is i had them indoors. Im guessing it was from bad soil that must have been infested. they are bitch and I had no idea to look out for them as they are hardly ever mentioned. I saw just one or two here and there at first thinking they were just little snails or something and then i come in one day and all the stems are covered in these bumpy things that pop off when you scrape at them. the plants were too far gone to help them.
I precisely wiehsd to say thanks once more. I am not sure the things I might have gone through in the absence of those points revealed by you directly on that area. Completely was an absolute alarming issue for me, however , looking at this well-written form you processed that forced me to cry with happiness. I’m just grateful for this information and trust you recognize what an amazing job you are always carrying out instructing the others with the aid of your webpage. Most probably you haven’t got to know any of us.
I have to show some appreciation to this wetrir just for bailing me out of this particular predicament. Just after checking throughout the online world and coming across concepts that were not pleasant, I thought my life was done. Being alive devoid of the solutions to the difficulties you have solved by way of this write-up is a serious case, as well as the ones that would have negatively affected my career if I hadn’t noticed your website. The competence and kindness in dealing with almost everything was vital. I am not sure what I would’ve done if I hadn’t come upon such a solution like this. I am able to at this moment relish my future. Thanks for your time very much for the reliable and amazing guide. I will not be reluctant to propose your site to anybody who desires counselling on this problem.
im in kern county and have encounteted a problem with the glassy winged sharpshooter attacking my plants. they suck them dry and give the plant a disease. little bastards!
[…] sure if whiteflies are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if snails and slugs are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if rats or mice are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
I saw a pure white blackwidow looking spider. What was it?
White widow what do you think
[…] sure if leaf miners are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if cats and dogs are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
[…] sure if gophers or moles are causing the damage to your marijuana plants? Check the article Marijuana pest and bug control for a list with pictures of all pests and […]
I have some sort of a bug problem and I can’t figure it out. I looked through all of your “pest” pictures but didn’t see any answers. This is eating a hole into the leaf, like what a slug would do, but also leaving a little pile of “poop” on the leaf. I’ve never seen a slug do this and I can’t see any slim or the iridescent trail that a slug or snail will leave. Any ideas?
Hi Terree, Join our support page. You can post pictures there and our expert growers will help you out.