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How To Get Rid Of Thrips On Your Marijuana Plants


Thrips and Cannabis

Thrips are tiny (less than 0,06″ in length), winged insects that feed on the juices of the cannabis plant by puncturing the plant and sucking up the contents within.  Although they wear wings, they are poor flyers and depend on the wind to carry them from venue to venue.  Their bodies are cigar shaped, with six legs and pointed butts.

The damage seen with thrips is evidenced by silver or bronze colored scars on the leaves and/or stems; wherever they have chosen to invade.  The leaves will be deprived of chlorophyll, turn brown, dry and crumbly.  Typically, they feed on developing flowers; this is where the damage to cannabis most occurs.  Thrips are known vectors for plant viruses, which is cause for concern.

Thrips are more of a threat to greenhouse gardens than those grown outdoors.  In either setting, they prefer the cannabis buds as the place to conduct their living habits.  If you see burned looking edges, you have a colony of thrips at work.  Shaking the plant will dislodge them and send them packing. Download my free marijuana grow bible to learn more tips and tricks for growing marijuana.

Predatory mites and parasitic wasps are natural deterrents to thrips attacking your marijuana plants.  Appling good compost mixture to the soil before planting will contain beneficial nematodes which attack any pupae that may fall to the ground.  Thrips are not a major threat in cannabis plants grown outdoors. Use neem oil or predatory mites to get rid of them. Also, if you want to protect your plants from bugs and disease, consider getting some of the products at this link here.

If you want to start growing, download my free grow guide and order some marijuana seeds. All top quality marijuana seeds are available in my marijuana seed shop. We ship seeds to the US, CA and many other countries. For any growing related question please visit the marijuana support page.

Source: ILoveGrowingMarijuana.Com



About Author

Robert Bergman is a master marijuana grower. Robert Bergman is the author of 'Marijuana Plant Care' and 'The Marijuana Grow Bible'.


  1. That’s strange, they seem to stay away from the buds on my plant, they chill on the lower half of the plant, this is the first time i’ve had a thripe infestation. It hit hard out of nowhere a week into flowering. I’ve been able to control them with neem when there were no flowers but now that i’m flowering i’ve been just power spraying the under-sides of leaves with plain water. The buds are growing very nicely so far, i’m crossing my fingers the stress of everything won’t affect yield.

  2. I grow outdoors and ONLY my buds are filled w thrips. Classic thrips just like in all photos you find in the web. I didnt know I had them til my first harvest and half my buds were just dust. Microscope proved it. As of today, all my plants have them bud just in the buds, which are all small as these havent been planted very long. Going to try spinosad on plant and hydrogen peroxide on soil

  3. Neem oil actually tastes nasty. Don’t do it. I have used it and it looked to me like it just suffocated them. Captain Jacks dead bug kills them. And don’t listen to anybody that thinks it’s ok to use and type of pesticides while flowers are forming. That’s amateur speculative science…… 18 of 40 tested pesticides vaporize below the temp if thc….

  4. Xavier McHenry on

    I’m a medical patient who grows their own and just got nailed by thrips because I didn’t remember to take off my shoes after mowing the lawn. (First time of the year and I was pretty baked). I never had them before, but after dealing with them I have some good facts for everyone, as well as helpful tips.

    1) Thrips attack leaves, but they do not go into your buds. I have an EcoPlus 60-100x zoom illuminated microscope. It’s great for checking your trichomes to see where they are on their maturity level. So when I found out I had thrips, I checked every bud that came from the infected plants. Not a single one was in the buds, and I had a pretty bad infestation.

    The reason for this is the trichomes themselves. Thrips won’t go near them because of how sticky they are. I saw a thrip stuck to a sugar leaf, little front legs wiggling madly, because it had ventured too close to a resin deposit. So thrips won’t get into your buds, they will just gnaw on your leaves. Bad, but not horrible.
    On a side note, people on another site were asking if thrips in the bud made the weed taste bad. I know they are not toxic, so I grabbed a few thrips and mashed them into a bud and smoked it. Gross, but for science, right? The worst it did was give it a little “early bud” taste…an almost undetectable chlorophyll taste. Which only fits because they are basically the cows of the insect kingdom. are green under a microscope and eat only leaves. Thus, even if the buds were infested with thrips, it wouldn’t effect the flavor much.

    2) Neem oil controls the problem. I didn’t say stops the problem, I said controls it. Especially if your grow area is cool and dry. Warm and humid breeds them like mad, so stay away from them if you see that. The only way to truly get rid of them is to remove all infected plants and clean the shit out of your grow area. And, of course, don’t put the infected plants back in.

    Neem oil doesn’t kill on contact. what it does is screw with the thrips so they don’t get hungry. Because they don’t eat, they starve to death. Take that, insect cow! That doesn’t mean they won’t leave eggs though. Neem is safe to spray on plants twice a week for 2-3 weeks with a decent, diluted coating, but be careful not to clog up the pores of the leaves with it. The plant can process the neem oil out of it, as it is a natural substance that is non-toxic to plants and humans. But if the plant gets too much, it can’t breathe. And yes, plants breathe.

    The same group wondering about smoking the thrips also wondered about smoking neem. Again, because it is non-toxic but no one had tried it, I did. You’re welcome. And I didn’t try it once. I wanted to find out just how close to harvest you could neem without problem. If it is within a week, it’s going to have a funky taste. Not bad per se’, just funky. Like sucking down a British ale when you are use to drinking wine coolers. No bad effects otherwise, but not a taste you would ever really get use to.
    Two weeks out from harvest as the last spraying and you barely notice it. I would actually make this my benchmark of the last moment you can spray and be good. Anything longer than 2 weeks and you are in the clear as long as you don’t overdo it with the neem.

    Not being an insect guy in general, I don’t say every thrip across the globe will be the same as I have, so if you live anywhere other than the northeastern area of the United States, it might be wise to get a microscope and check through your buds to make sure you don’t have any there, but I’m pretty sure the resin keeps all of them out. But, not being an expert on the subject, it’s better safe than sorry.

    Hope being a guinea pig helps others with their problems.

  5. It is important to address which thrips species you are dealing with so you can get the right beneficial. Not all thrips biologies are the same, and beneficial neamtodes so not work on all thrips species. Also the predatory mites only feed on the first instart of thrips, not controlling the adults or pupa stage.

  6. Coca Panther, you should try something stronger than neem. Like Azamax and Spinosad which is a good combo that kills spider mites. You need to really spray the undersides of the leaf, as well as the top.

  7. Coca panther on

    what do you think I may be having? I thought of spider mite, not sure, just started. on the leaves i could find kind of “sticky” web white/pinkish, some “dots” red, black, white like dust or small things….nothing “moving” when I look with the magnifying glass… I am spraying at night with neem/water, spraying soil and surrounding area too. What could be? what else could I do? they are 1 1/2 months old….

  8. Gary In The Desert on

    Just got out my magnifying glass and yes I have the little things but I can’t take the plant outside and shake it as it is in my den and growing. What spray if any do you recommend?

  9. Only if they were brought In your room by soil, clone, or carried off clothing from an infected site, never let others touch your plts

  10. If your in a tent and not past week six in the bloom stage I suggest dropping a bomb, pyrethian spray for main branchesand merit for soil

  11. Depending on size of pot and how much water your using, every 36 hours is a good schedule

  12. Hi guys new to the forum
    the names shag by the way, iv got frips and spider mite would co2 in a sealed tent kill

  13. Justin @ Budski.net on

    Strange that these aren’t a problem for outdoor grows, I guess keeping a sterile indoors grow environment would prevent these, or would they still present a problem?

    Justin @ Budski.net

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