I think I have spider mites in mid flower. Need recommendation for effective treatment.

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Stresscookie

Stresscookie

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Hi. Newbie here in fear of losing my crop.
I noticed white spots on lower leaves a while back but saw noting happening on the under side. Couldn't find anything like it online. Also have had issues with powdery mold on my soil. Humidity has been as issue for me. Everything seemed under control until I got a better dehumidifier and finally got it down under 50%. In the past few days things seemed to be getting worse. In looking for solutions today I found out the mature when the humidity drops. Go figure.
I really can't afford to lose this crop. Help.
I
I think i have spider mites in mid flower need recommendation for effective treatment
I think i have spider mites in mid flower need recommendation for effective treatment 2
I think i have spider mites in mid flower need recommendation for effective treatment 3
 
Stresscookie

Stresscookie

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A couple of notes after scanning the "read me" thread...
There is a bunch of information in my introductory post about my plants re: soil, fertilizer, watering and general conditions
The plants are grown from seed I harvested out of pot I had purchased. I use for medicinal purposes. Hoping I could save myself a great deal of money (LOL)
I began unprepared and without any horticultural skill. Growing for personal use on a tight budget, in an apartment. To be honest, I am finding it all a little overwhelming. There are so many different approaches out there...
The grow space is 39"x39"x80" and I am using a MARS HYDRO TS 600W. I know this is not ideal. It was the best I can do on my budget. There are 5, 8" clip fans, one vented as an exhaust and 2 as intakes, top and bottom; the other two just move air. One above the canopy and one at the base of the 3 plants. There were 6 fans, but I had to remove one to get the dehumidifier plugged in. i have, for the moment, turned off the dehumidifier. I have yet to replace it with the fan again. From what I read earlier about spider mites, i think that the reduction in humidity and air flow may have been factors in things getting worse.
As noted in this post, I thought I might have been dealing with mould. I found some household remedies and decided to try a wash with a mix of baking soda, dish soap and water. I have read that spraying during flowering is bad. So, I used paper towels and wiped all of the fan leaves with it before I got the dehumidifier on Monday. Gave the tent a good once over as well. The temperature is currently about 25C/77F and the humidity is down to about 35% from 50-60%.
Not sure what else to add. I could really use some good advice on effective and economical ways to deal with this quickly.
Thanks
 
mancorn

mancorn

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Ton of threads on mites/thrips, so do a forum search. Cheapest “solution“ is spraying the lower leaves with water. Use a spray bottle so you can blast the leaves. Or take into your kitchen if you have a good faucet sprayer. This will not kill the mites, but will slow them down and knock them off the leaves and maybe get you to harvest if you’re persistent. If you can get the spinosad that will be a huge help. It’s fairly cheap, available at most garden center/hardware stores and safe.
 
Stresscookie

Stresscookie

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Sadly, doesn't look like I can get spinosad in Canada. Or blue sticky strips for that matter. Found a potassium salt based insecticide I am going to try I think. Suggested for thrips in another thread.
 
mancorn

mancorn

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Sadly, doesn't look like I can get spinosad in Canada. Or blue sticky strips for that matter. Found a potassium salt based insecticide I am going to try I think. Suggested for thrips in another thread.

You can make a neem spray from cake meal. (Box cost about $20). Let the cake seep in water for a couple days and then spray leaves and dirt. It’s not an oil but still has a strong smell, so I’d avoid spraying the buds directly.
 
Flexnerb

Flexnerb

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You might have got lucky it might be thrips, why don't you search pictures of 'thrip damage on cannabis' and see what you think;

If it's thrips I used Monterey with spinosad with great success

The one thing you don't want to use is neem oil on a flowering plant, good luck!
cant get any of it on amazon.ca
:(

Soapy water ivory or liquid castile soap
Few drops in water.
I used peroxide and vinegar switched back and fourth between the two. They have 4 instars before adulthood. Gotta get at them in the soil too...

Can you get 35% food grade hydrogen peroxide? 8% 12% even 3% its gotta be "food grade". Dilute to .5% kills fungus gnat larvae. Maybe that would work too


I would not use neem oil or neem anything unless you got neem seed meal. Mix that globally when you mix your soil up. Neem for budding plants is bad unless its used in the first week maybe 2 into flowering.

Maybe someone could send this kind fella some spinosad!!
 
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Anthem

Anthem

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I have not tried this but it seems like a reasonable way to put a pitch fork in those suckers
 
Twenty20

Twenty20

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You might have got lucky it might be thrips, why don't you search pictures of 'thrip damage on cannabis' and see what you think;

If it's thrips I used Monterey with spinosad with great success

The one thing you don't want to use is neem oil on a flowering plant, good luck!
Hi. Newbie here in fear of losing my crop.
I noticed white spots on lower leaves a while back but saw noting happening on the under side. Couldn't find anything like it online. Also have had issues with powdery mold on my soil. Humidity has been as issue for me. Everything seemed under control until I got a better dehumidifier and finally got it down under 50%. In the past few days things seemed to be getting worse. In looking for solutions today I found out the mature when the humidity drops. Go figure.
I really can't afford to lose this crop. Help.
I View attachment 1016249View attachment 1016250View attachment 1016307
I agree with @Beachwalker . I believe those are Thrips. They are hard to get rid of completely but they do much less damage than two-spotted spider mites. We use a product called PureCrop1 in our cultivation facility and it takes care of most soft-bodied insects after a few applications.
 
Stresscookie

Stresscookie

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Thanks to everyone for the input. This is my very first grow. And, I went into it completely blind. I am not a horticulturalist. I have been hacking it out along the way. (At some point, I will post pics of the original tent I Macgyvered with a couple of clothes racks, some Mylar emergency blankets and big piece of cardboard! I only bought an actual tent because I didn't have the height to raise the light enough.) I really appreciate being able to tap your wisdom!
It turns out, fungus gnats are definitely part, if not all, of the equation. I did end up finding a few dead ones. And, I did have an early issue with them, (although they were bigger flies) that I thought I had handled with cinnamon (I have read a lot about using "hot" spices to combat pests. Thanks @Anthem for the pitchfork idea! I used cinnamon at the time because it was handy and in the moderate range of things. I have been trying to tread carefully). I guess I just kept them at bay. I didn't realize that I was over watering and probably over feeding. I thought I was being fairly moderate. I think that may also have to do with my soil choice. The strange part was the leaves started to get worse when I finally got my humidity down... it did get a little low. I did not expect that.
Based on my research, I got some castile soap and made a simple insecticidal soap. Wiped the fan leaves rather than spraying to avoid the buds. Also picked up some beneficial nematodes and threw them in a couple of days ago. I will probably do that again at least once. I could do a 3rd although it would be lighter - there were 8 pouches in the package. I have 3 plants.
Many sites advise to use a variety of approaches. Next in the lineup, if necessary, is Diatomaceous earth.
I lost a couple of lower fan leaves. One was really shaded and had a lot damage, so, I chose to cut it. The other snapped halfway up it's stem somehow when I was reaching past that plant to examine another. I really was surprised as I didn't think i did more than brush it.
Getting to the point, I am confused if I should trim damaged leaves. I have also had concerns about possible deficiencies. Haven't really known what or if to supplement given the soil and food choices I made to start.
I am a month into flower. One of my plants seems to be lagging behind the other two. Fingers crossed I haven't done more harm than good.
These pics are a week old. One bud from each plant. The one hasn't progressed much at all. Any additional insight you all could lend would be greatly appreciated!
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Twenty20

Twenty20

Supporter
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Trimming off damaged leaves and especially infested leaves won;t hurt anything. Heck, some people strip the entire plant (I don't condone that method but some people swear by it) I think your plants look great and they should be just fine. Fungus gnats don't really cause damage except they are annoying and they can carry pathogens from one plant to another. A general rule of thumb: If you have bad fungus gnats in soil, your room is likely too humid or you are overwatering.
cheers
 
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