Just checked all of them. Which do you recommend more though, mosquito bits or gnatrol? Does mosquito bits kill the larvae on contact? The gnatrol says larvae will die within a week of contact

The larvae have to feed on the Bt-I. Did you look up what it is and how it works? It's a biological control.....extremely effective but not a contact killer.

HERE are some informative links that will help you learn what this stuff is. I like the liquid as well as the granules.....it simply depends upon your preference. It is the same active ingredient.

Yes I looked it up but there doesn't seem to be any liquid versions.. just granulars that you can soak with water. If this doesn't work then I will repot all 3 of my citrus even though 2 of them were just potted couple months ago...

Fungus gnats can be an indicator that there's too much moisture trapped in the potting medium. I might just let the pot dry out a bit more between waterings, that's usually enough to break the life cycle of the gnats without worrying about sprays and the like. My plants in 5-1-1 have typically been completely gnat-free, and it's only the houseplants in organic potting mix that ever get them.

I had a big "problem" with fungus gnats. They were just annoying.

My rescue seemed to be big colonies of soil/predatory mites. Hundreds of them. Came out of nowhere, but I dont complain.

They are hypoaspis miles, they look very similar to those.

Thats one option. Although not the fastest one.

https://en.m.wikipedia.org/wiki/Hypoaspis_miles

Soak the medium with horticultural oil and water, as per the bottle instructions directions for mixing up a spray. Maybe make it a bit more concentrated.

I was having a nasty gnat problem until I started spraying my trees with hort oil. After about 3 applications of foliage as well as drenching the soul/medium, the gnats disappeared and have not come back.

Soak the mosquito bits or broken up mosquito dunks in water overnight. A teaspoon in 1 gallon water is plenty. You can use this with your regular watering and it will take care of the gnats. I usually, sprinkle a tiny bit of the powder for seedlings and cuttings since there is little airflow to keep the humidity up in a confined space.

To prevent though you will have to make sure the top dries out before next watering and provide plenty of airflow. Remove dead leaves from the soil surface frequently so that they have nothing much to feed on. Keep the saucers clean of organic matter too.

I have read that you can use a slice of potato as a bait and the larvae will prefer that. Keep replacing the potato slice every few days. I have not tried this but seems it may work.

You must be patient when using Gnatrol -- takes at least 6 weeks to break the gnats' life cycle.

I just remembered that someone once posted a video of a guy using neem cake in water to get rid of gnats. I haven't tried it, but next time I get bugged by gnats I may look into that. keeping my mix drier (and going less peat) took care of my gnat problems.

So is gnatrol 100% guaranteed to work? If not, I don't think it makes sense to wait 6 weeks just to find out its not working.

Gahhh now I found spider mites on my yuzu!! This sucks, spider mites like dry conditions and gnats like moist conditions.. wth am I supposed to do?

Spidermites likes low AIR hudminity and fungus gnata likes moist SOIL, so let the soil dry out between waterings and mist your plants regularly.

We have very dry air during wintertime, and I mist ALL of my plants at morning and ar evening. Including all of my "regular" housplants. Never had an issue with spidermites.

If Im home the whole day, I mist probably 4-5 times a day. And during watering I spray the whole plants quit hardly.

Another simple way to address this issue is to water the plant from the bottom-up. I pour water into the bottom tray in small quantities every 2 days or so and the plant wicks the water up. This way the moisture is deeper in the container and the gnats are deprived of their water to multiply. Even if they do get some moisture, they cant find their way out from the bottom of the soil. After the gnats disappear if weather permits to keep the pot outside in a couple of weeks, I give the plant a thorough watering from top and keep the pot out in the shade until the top dries up.

Once again, horticultural oil, drench foliage and mix every few days for a couple weeks then switch to maintenance mode. Done.

Using the mosquito granules (same as gnatrol) has worked beautifully for me.

I used the Gnatrol for about 2 months and it did not work. I then used Gnat Nix and it worked within a month.

I don't get it. Why is it that for some people it works and for some it doesn't? Do each fungus gnat have different strengths and tolerations? I will try the water on the bottom method. That way I guess the fungus gnats can't come out from the bottom and I will add more coarse sand on the surface so they can't get out.

I also have 3 yellow sticky traps on each pot, and 2 sticky straps hanging right behind it, and small container with soapy water in it to drown them. With all of that I have probably killed at least 30,000 gnats but the population doesn't seem to be decreasing. Could they be coming from a different source inside my house? The only houseplants I have now are the 3 citruses that are infested with the gnats.

Oh and on top of that, I kill about 30-40 of them with my fingers everytime I come back home from work. Thats when I see them the most around my pots for some reason

That sounds like a war zone. 3 citrus plants and all that fungus gnats. I think there is a more basic problem here. Soil mix that does not drain well and/or has lot of organic matter, too much watering and very little air movement will be my primary suspects.

Mosquito bits, Gnatrol, GnatNix all supposedly have the same active bacteria that kills the larvae. I only use the Mosquito bits - mainly for my small outdoor pond to kill the mosquito larva. Works wonderfully without fail. And to a much lesser extent I use it for cuttings and seedlings since they are grown in high humidity environment. I just sprinkle a tiny bit of crushed mosquito bits. Works without fail.

I use 5-1-1 mix(reptibark) for my yuzu and satsuma mandarin but I use stagreen potting mix amended with reptibark for my sudachi. The Gnat infestation started from my sudachi and spread to my yuzu and satsuma mandarin. I don't understand why they continue to thrive in my 5-1-1 mixed yuzu and satsuma mandarin though. It's super fast draining like the water comes out from the bottom not even 5 seconds after watering. And I haven't watered any of my plants in 2 weeks. I also have loads of coarse sand on the surface so the gnats shouldn't be able to get in but somehow they do. I put tons of hydrogen peroxide and insecticidal soap but didn't work. People say it's the watering issue but it's not. Before I only watered once a week and now I haven't watered in 2 weeks! Plus it's reptibark instead of pine bark so it should dry up faster.

May be the infestation is only in one pot and it just looks like other ones are infested too. Have you tried using a small fan? It makes life difficult for those tiny flying insects by creating a turbulent environment.

I would try taking the plant out of its pot and look for signs of other kind of infestation like root aphids. The adult flying version of root aphids can also be confused with fungus gnats. Root aphids are generally hard to get rid of once established. I have read somewhere that it has become increasingly common in commercially bagged potting soil from large companies.

Hydrogen peroxide is mainly used in soil to prevent root rot. Although I have my doubts about its eventual effectiveness. I do not think it is really effective against soil dwelling insects. Insecticidal soap in soil is generally advised against because it can potentially damage the fine roots. A better way would be to soak the pot for an hr or two in pyrethrin solution. Probably neem solution will be OK too. Not sure.

I just read all the posts starting with your original in Jan. and noticed that no one has mentioned surrounding areas where these pesky things will reproduce. All wet areas have to be eliminated. I have a buddy that has been battling these things for months as well and is finally getting ahead of the game. The combination of things that have worked best in my circle are: Fly paper and sticky traps, the bottle traps with cider vinegar ( multiple ), any catch pans under containers sealed with saran wrap, 2" of dry mulch on top of planter soil ( the gnats won't go deeper than a couple of inches) and check the rest of the room for wet spots.

When I was having the biggest problems, I discovered they were in my dehumidifier when they finally plugged the drain tube!

Jean is absolutely correct about breaking the cycle, it takes at least 6 weeks!

Hope this helps, I know how frustrating it is.

Thanks for the help. Got a new question now. Can fungus gnat larvae live in water? What I did was poured some water on the bottom of the pot(on saucer) and sprayed some insecticidal soap in the water as well. Now I'm seeing a lot of dead gnats in the water but I also see lots of sunken+floating larvae. I'm wondering if the larvae are dead or living in the water. I've never seen a mass of larvaes like this before.

How did the larvae end up in the saucer below? At this point some sort of picture will be useful. The way you are describing it should be easy to take a picture of.

Soap solution would likely kill larvae but they can probably live in water without soap. But they would need some organic matter to feed on. Mosquito larvae does but they stay near the surface to breathe. I am sure there are others that can too.

Adults probably fly into the water and are killed by soap. Fruit flies do the same.

If it is indeed fungus gnats then using mosquito bits/dunks/gnatrol/etc would have have reduced the population within a week - unless you have another source somewhere in the surroundings. At the very least you would know whether it is fungus gnats or something else. At this point you would have to use those options. You seem to have a severe infestation of something and watering from bottom/top or any other such means or adding sand is not going to control it. Nuke it first and then evaluate your other options.

I have no idea.. I want to know myself. I ordered mosquito bits on Amazon today Btw. Let's see how it does. Here's the pic of it. The larvae is in the center of the pic and I think it's dead. Another pic shows all the gnats I caught. Not even close to a tenth of the total I killed so far Btw.

Now the fungus gnats have infested my new calamondin. Others are almost totally clean of those suckers. Reason for that is the calamondin has a sort of gritty mix, and soil mites doesnt seem to like it. Every other plant I have does have soil mites, hundreds of them.

Perhaps if I top dress the gritty mix with some 5-1-1 I could make a better enviroment for soil mites.

Ok so the mosquito bits came yesterday and I soaked it overnight and then watered my 2 citrus this morning. Do the larvae eat the bits itself? Or does the bacteria in it kill them? Because the bits tend to stay on the surface and won't go in deep in the mix. So I don't know if the larvae will come to the surface to eat the bits.

Another concern. When I was removing the coarse sand from the surface, I accidently ripped a thin root of one of my citrus that was attached to the trunk. Is that gonna harm my citrus? They are showing signs of new growth now

The bacteria in the bits kills the larvae. Don't worry those bacteria will be everywhere in the soil. I usually sprinkle it in dry form on the soil surface. I only tend to get some fungus gnats in my cuttings/seedlings area where the humidity is high and not much air flow. But I just do it once and that is enough. In your case, let the soil dry out and repeat the application next the time you water.

A few roots ripped should not be a problem. I am sure there are many more in the soil. Start giving them 1/4-1/2 strength fertilizer, plenty of light, good airflow and you should notice good growth in a week or two.

Ok I guess I did the right thing then. But for the roots, the one I ripped was very thin but was attached to the trunk which means it is one of the main roots and not the feeder roots. Isn't it bad if one of the main roots get damaged? I was planning on fertilizing once spring actually comes and when I bring them outdoors. Or should I start now?

I usually fertilize at 1/4 strength all through winter and most others do too if the plants are not dormant. Like my dormant plumeria get some plain water once every month or so now. Most of my other plants are growing slowly or just hanging in there - I actually like that since space is limited. Some of them have started pushing new growth in earnest and for those I increase the fertilizer to 1/2 strength - eg my pomegranate came out of dormancy and is flush with new leaves - against my hopes.

So you should fertilize especially since it is showing some signs of new growth. Start with quarter strength and see how it responds.

Ok will do but since I just watered this morning, I'm gonna have to wait like another 2 weeks for my next watering since it doesn't dry up until then.

Good. That should not be a problem. If it starts taking off it may suck that water off quicker than before. That will be a good sign.

Ok so its been about 4 weeks since I first used mosquito bits on my 2 citrus and I've watered them with overnight soaked gnatrol a total of 3 times so far for the past 4 weeks. While I thought there were improvements, things are just getting worse. I see baby gnats flying all around the soil and the window. I had to get an insecticidal soap to kill all those little pests on the soil and I smashed the rest with my fingers. Whats going on? I thought mosquito bits are supposed to kill the larvae? I guess I'm unlucky when it comes to citrus gardening then. Why are all my gnats immortal while all of yours just go away for you whatever you do to it?

Would replacing the top of the soil 2-3 inches make a difference? Do the larvae go deep in the soil or do they tend to stick on the shallower parts of the soil?

Heruga, I'm sorry you are having so much trouble. I had fungus gnats through most of the winter, and although annoying, they did not cause any harm. I did not do much other than use those yellow sticky traps. I ready someone here mention that they are especially drawn to new mixes - the fresh peat moss in particular. This is exactly what I saw. The trees that were in fresh mixes had them while the others did not. Eventually even those stopped having a problem also. I would NOT change the top layer. Are your trees ok? Are they growing? If so, I would not worry about it too much.

Sounds like a strange problem indeed. I have never seen this problem at this scale that even the mosquito bits cannot handle in the short run. Next time you are repotting, examine the soil carefully to look for clues. And I would suggest to bare root and use the 511 mix.

Fungus gnats larvae will attack the fine roots and cause quite a bit of stress for the plants. Depends on how badly infested it is.

I use peat moss from miracle gro. I also use 3 of those yellow sticky traps on each plant too. The trees are perfectly ok. Other than my Yuzu no showing any new signs of growth they both are doing fine.

Tropicofcancer, I have been using 5-1-1 mix the whole time. Have you been reading my previous posts? Despite using mosquito bits, daily killing of at least 50 gnats with my fingers, using insecticidal soap, using hydrogen peroxide, having 3 yellow sticky traps on each plant, having 2 sticky straps hanging behind the plants, adding pebbles over the surface of the soil in hopes of gnats not being able to get in the soil to reproduce, there are still so many gnats flying around everywhere. I think I've discovered a new species of insect called immortal fungus gnats lol

It has been a while and I do not remember the details in earlier posts - apologies.

So I presume you bare-rooted when repotting? That is all the old soil mix was washed off. And the peat moss is just peat and no compost? May be you already answered this but I am too lazy to scroll back.

Otherwise it is a mystery indeed. I have 150+ plants in several variations of 511, gritty and other bonsai like mixes. Once in a while I will see a small flying insect or two. Never bothered to find out what they are since they just vanish away.

Well this is the first time I potted my yuzu and satsuma mandarin. When it came to my mail, I took out the potted trees from their pot and potted it in my pot with the 5-1-1 mix. I didn't scrape off the existing potting soil because all their roots were in it and otherwise I would've damaged them. The peat moss is miracle gro and it is sphagnum peat moss and I don't think there is any compost in it.

The weird thing is, I repotted my sudachi like a month ago bareroot(I was able to soak it and wash off all the soil with this one) and potted it in 5-1-1 mix but I still see some fungus gnats here and there on it. Not an infestation. So I don't think potting it bareroot would really make a difference would it?

I would bare root those trees now in the spring (next few weeks) once the temps are warm and stable. I would also re-use the 5-1-1 you already have. Depending on how much peat moss you added, you may want to add a bit more bark and perlite. I do not use exactly 5-1-1...more like 5-2-.5. My experience totallly agrees with what someone mentioned here (I wish I could remember who it was) - that fungus gnats go for the new mixes with fresh peat moss. I suspect that after a month or so outside, they will be gone and that you will not have this problem next winter. My trees in the old 5-1-1 mixes did not have any gnat problems.

I was thinking of repotting them but I'm a little hesitant because if I repot them, I can't put them out in the sun for a couple weeks right? So then that means it'll delay growth.. but I guess I have no choice.. So being outside would attract less fungus gnats than indoors?

I just did a full bare root on my NZL over the weekend, and found soaking the rootball in a 5 gallon bucket of water for 15 minutes and then swishing the root ball through the water quickly while loosening the mix with my fingers for another 5 minutes got 75% of the soil off then with a jug of water (or a hose if you have one handy) I focused the stream on the places that still had clumps of dirt and used my fingers to gently push them out. There was only a few chucks of bark left fused to the roots when I was done.

If it was a soil mix they were in you might be surprised at how much moisture is in the root mass and that might be why there is more fungus gnats. Outdoors probably has better air circulation and would help control the moisture level better, but soil on those roots may cause a rot problem down the road. I would repot now, just to save me the trouble later but you could always wait.

Did you try the neem-cake + water solution? mikerno_1micha posted a link to a video about it here. If I ever have gnat problems inside again, I'll be trying it. Here's the post about it:

http://forums.gardenweb.com/discussions/4340504/have-you-ever-tried-this-for-fungus-gnats-and-other-soil-pests?n=3

Ok I will definitely repot it. Sometime in April I will. But what do u mean all sorts of problems with not bare rooting it. Will the plants die from too much stress of moving into a new potting mix if they go in a pot with their old potting mix? It's been 4 months since I first potted the citrus but they don't seem to be stressed

What I mean is if you are going to put it in 511 mix without bare-rooting you end up with a plant that has to now deal with two different mediums in its root zone. Not a good thing at all. You will end up in one of two situations: The inner core is always wet and the outer layer of 511 that is dry. This will lead to root rot. And if the old soil had fungus gnats or other pests they will have field day indoors. Or if the inner core dries up for some reason then it becomes hydrophobic (if it is peat based which is quite likely) and it will have a hard time wetting again. Water will find the fastest path in the outside 511 and the inner core will remain dry. This will lead to root death. So no matter what you choose the entire soil mix should be of similar type.

The best evidence of above mismatch happens when inexperienced landscapers plant a tree in the yard. They dig a hole, put a plant with a tight root ball of a different mix, fill the hole with another soil mix, and call it done. In this case the plant is now faced with three different soil. In practice, I have seen countless trees die in such a situation.

May be you are already familiar but here is a repot process.

Water the plant well before you repot. Wait a day if you can before you start. Have your pot and mix ready. Mix should be just moist not dripping wet. For tropicals June is considered the best time. They are the strongest then. But I have done it in April through September.

When you repot, keep the roots moist at all times. Have a bucket of water and/or mister ready. Work the soil out with a chopstick, a screwdriver, etc. Every few minutes mist or dunk in water to keep the roots happy. Citrus roots are a bit fragile and some will just break off. Just keep going.The plant will be OK. If it is hard to tease out the soil then use a hose at flat/jet setting and go very easy on the trigger. You want to wash the soil off gently.

I usually mound up the soil in a upright cone form in the new pot. Then place the plant on top of the cone of soil and have the roots spread out like a big "skirt" nearly flat and hugging the cone. Add handful of mix at a time and use a chopstick to push around the roots. Work the centre first and then the outer edges. Do a jiggle test to make sure the plant does not move around too much. Once done water well, keep in a shaded, warm spot protected from wind.

I prefer to do when it is cool (below 70F), calm and cloudy if I am doing it outdoors. Many times I have even left the plant in the bucket of water half bare-rooted overnight and finished the next day without any problems.

I see what your saying now. So even plants that you plant in the ground have to be bare rooted you're saying?

Also I planted 5 conifers couple of weeks ago in 5-1-1 mix without making it bare root. Do I have to make all 5 of them bare root and re pot them again? The conifers are seedlings and don't really have a big root system yet btw.

In the ground you can use other techniques without bare rooting. Bare rooting a more mature plants is more stressful for the plant. A young plant will recover much quicker. Sort of like us humans. It gets much harder to fix a broken bone as one gets older. The common way to deal with a mature tree like plant in ground is to first break up the root ball a bit. Rake out some of the soil from the root ball. Expose outer roots a bit and spread them out. Then blend in native soil, compost, top soil so that it gradually changes from one soil type to the other. To the extent it is possible depending on skill.

A young plant of few years old is much stronger and able to recover quicker. I am sure everyone is thinking that is not true - but it is in general. You can take a tomato seedling and gently pull it out of soil and plant it somewhere else and it will not miss a beat. I get many such volunteer tomato seedlings (heirlooms) in late spring in the yard and just yank it out of the ground using my fingers as a fork to dig in around it and replant them in my desired spot with no problems. They are stronger plants and establish and grow much faster. I never start them indoors unless it is a new variety. With store bought annuals plugs I would gently crush the root ball between my palms and plant it. That is enough to make the soil blend in.

Conifers tolerate bare-rooting when they are just pushing new growth and that happens around late spring. If your conifers are just baby plants (1-2 yr olds) they should be fine. I am assuming they are in containers. In ground you should not be using a 511 mix anyway. You can rake the base of the plant a bit with a chopstick and blend in the 511 into the original root ball a bit. Mugho pine should be bare-rooted later - late summer usually.

Thanks. Yea thats what I do for in ground and I'm more experienced planting stuff in the ground than in pots. I was confused because I've never heard of bare rooting for plants to go in the ground.

Ok so they are fine the way they are now? No root rot will occur? Yes they are in pots, not in the ground.

If it came in a 3-4 inch pot then rake base of the plants to blend the surrounding mix. May be do it once again a month later. I am assuming you have small 4 inch pot type plant. If it is larger then you are better of bare-rooting and replacing the soil.

Conifers would prefer a more airy soil. So I would choose gritty mix over 511. They will much happier in gritty. Or you can make it 520 without peat and more perlite. Either way it will be better to then change the entire mix - that is bare-root.

I got a 4inch pot of scotts pine last year that was up-potted in a
520-ish mix. I blended the soil a bit then. This year it will be
bare-rooted and put in gritty mix. I should have done it last year but it was too late in the season.

I don't remember how many inches the pots were but the seedlings were about 16-20 inches tall and one was in a gallon pot and one was in a quart pot. Are those too big that I would need to bare root it?

I would bare-root and repot. Here is a link that discusses evergreen repotting. It is a bonsai site but the same principles apply. Since it is a young plant it will recover fast.