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Questions about Thrips


New Member
About 10 days ago i found thrips in 4 week of flower i didn't want to spray them with anything because i smoke what i make and i really don't trust anything even if it says it safe to spray when flower. I noticed that they were only on lower leaves so i removed them and spray them with water to remove as much of them as i could and it seems ok i noticed only two till now so this flowers will finish just ok. But today i noticed them in my veg room which its not terrible because plants are only 2 weeks old and have just top leaves and i can spray them. But where did they came from soil or from outside? Are they hidding in soil? Will i be able to remove them from my flower room when i finish if i will throw soil out and disinfect room with alcohol? Will organic pyrethrin kill them?


Well-Known Member
Nuke them from orbit..its the only way to be sure.......:(

I have dealt with Thrips quite a bit in a Glasshouse situation. You need to research what insecticides are available in your locality for thrips, get two or three of them (each in a different class) . Spray with one, then 5 days later spray same one again, then 5 days later spray with a different one. That helps break the breeding cycle and hopefully gets any Thrips resistant to the first one you sprayed. When spraying do from underneath as well as from the top.

The BIG problem with Thrips is that as a population they can pick up resistance VERY quickly and the resistances in the population can be very local. When spraying do from underneath as well as from the top.

Hopfully that will get em off your plants. :) Seriously, you will need to do a VERY comprehensive clean of you room between grows or they will be back. Here, in our GH's, we close em up from time to time with the air con off in summer ant let the GH do to 50 degrees C or so for a few days. :) And, we fumigate with Flea bombs (like people use in their house)every now and again.

Hey..you may be lucky and find something organic that will work. I'd try Neem oil and then a pyrethrin as first attempt.

Have a look at this:

Blue stickies very useful and, if your doing a continuous grow and are willing to make the time commitment, maybe the Integrated Pest Management approach with predator insects. Warcraft in the Growroom?? :)

I have a bit more relaxed attitude to chemicals due to my professional background. However i do respect those who wont use em and get really pissed at people who use em badly. Prefer not to use them myself but am cognizant of withholding periods and that sometimes, for pests like Thrips just have to do it. :(

Sympathies, and good luck.

Bush Doctor 77

Well-Known Member
Welcome. You could use neem/dish soap on the plants in veg. It's a tough decision on the mid-bloom stuff. Myself, I'd spray the stuff in bloom, too. That's about the latest I'd do it though. If you are really concerned about residue, do a neem/dish soap spray then a warm dish soap mix, then warm RO for a rinse. You can put pretty warm water in your sprayer, because the spray will cool in the air. Test it on your hand.


New Member
OK you two definitely didn't put my mind to rest :D i am now terrified o_O

First to address my plants in flower i check them couple times per day and in 10 days i have found 2 thrips so they have around 2 weeks to end so i will leave them alone. And i really don't trust any spray in flower not even neem oil i have read that is not that safe but then again i just read that on internet so...no but really i am reluctant to use anything in flower.. the ones in veg i have sprayed yesterday with this en.unichem.si - Product this is what i could get and i know i can also get neem oil but than that is about it.

I have heard that blue stickies are the way to go but i assume it works only with thrips in flying stage but i haven't found any with wings so i don't know how effective would they be.

About predatory insect i wanted to buy them but i can't get any locally and in other EU countries i find them but then they ship only locally

i think i can manage them in my veg room because plants are really small and is impossible to miss a spot but i am worried that this will be persistent problem. Because this is in house i don't have many options.

So do you advice when i will finish those plantsin 14 days that i chop, trim and dry them in same room where they where flowering and after they are dryed i put them in jars and clean the room right? so i don't dry them in other place and also transfer thrips all over my house

Also if i can get rid of them now and if they didn't came from soil i shouldn't have them back for at least half year because it will soon be too cold outside

Both of you thanks for help i really appriciate it.

this is flower room (i didn't bother making photo in normal light sorry)

veg room with parsley :D

damage from thrips on lower leaves(also a little bit of mag def). But i can't find any thrips on it...strange


Well-Known Member
In veg. I recommend you looking into spindosid organic and will take care of your problem before it gets out of hand. Deep clean disinfect everything you'll be fine. I believe the product is called caption jacks dead bug spindosid. Good luck.

Bush Doctor 77

Well-Known Member
Nice good reads ill stick 2 spindosid lol neem leaves I think oily residue on plants where spindosid does not my2cents 2 each their own eh.
Important to me is the relative half live of each. Neem, half will be gone in 2 days max, while Spinosad has a 16 day max half life. Neem in 16 days will have .2% left, Spinosad will have 50% remaining. Neem degrades 8X faster.


New Member
Yea i am also a little put of by neem oil oil :) But is this spinosad in dust form ok? Anyone has any expirience with it? it doesn't seems smart spreding all that dust around in house.

I just checked about spinosad and you need to have a permit to be able to buy it in EU like for most chems here so either dust spinosad from post above or no spinosad :)
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Orlando Scout

Well-Known Member
I agree with @scrogster on the spinosad, and neem most definitely leaves a nasty smelling residue. I’ve also use iso alcohol at a dilution of 1to9. Seemed to kill them on contact for me plus it’s safe to use in flower, and the alcohol evaporates extremely fast so no worry about residue!!
Hope you find a cure!!


New Member
yea i would love to get a hold of something but its hard to get because i need permit for almost everything. I am now thinking i will just wait till i chop my plants on sunday and kill off all other plants in my veg room and clean everything with alcohol wait for 1 week and restart with new plants it just seems that i can't get rid of them any other way and i don't even know it that will get rid of them what do you think?
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