I spray the surface of the soil with insecticidal soap, repeatedly. I think it works, but the plants eventually head outside in late spring where they get the new does of pests..

We had a gnat issue with our Yucca. We found this remedy. Before watering the house plants, mix in a tablespoon of soap and a teaspoon of white vinegar. The plant is healthy and gnat free. I do this every other watering.

I've read that neem oil spray does the trick. Also, someone advised me that watering my plants from the bottom (allowing the plants to soak up water) would prevent pests. I haven't tried either, however, so not sure how well they work.

not sure if this was one of your google answers that didn't work, but putting out a little cup of cider vinegar works very well. i go an extra step and put a piece of plastic wrap over the top and poke tiny holes in it with a fork, works like a charm to catch the ones that buzz around.

I had the same problem! I tried watering with soapy water, and spraying the surface of the soil with Safer's, but nothing worked.

I eventually took them all out of the soil and am growing them hydroponically. It has elliminated the gnats, but it was alot of work.

The plants will go back into pots of soil for the summer when they go outside, but I will probably put them back in plain water if and when I bring them back in for the winter again.

If your gnat is about the size of a fruit fly, but has longer legs, then its a fungus gnat. They proliferate in moist soil - so make sure you are not over-watering. Also, you can buy "gnatrol" - a natural bacillus toxin to add to water. This will kill the larvae, but plants have to be treated several times - like every 2 weeks for 6 weeks total. Its very effective as long as you are not also fertilizing.

In addition to what lazy_lurker said, there inexpensive products called sticky stakes that will catch the flying gnats until the soil dries enough that insects are no longer hatching.

I have always used moth balls in the dirt of the plant, it has always eliminated gnats and any bugs in the soil. It does not seem to affect the plant at all. I would say 1 or 2 moth balls in a 12 inch pot.

I had to take the plants out of the pots, wash them entirely in the tub, toss out the soil, bleach the pots. Then I sterilized the soil in the oven. The knats have been gone, but it's a nasty dirty process. I can't however seem to get rid of the scales infesting my aloe plant. I'm about to give up on that one.

I used to get these tiny gnats, smaller than fruit flies, and I think it was from bug eggs on the surface that were able to hatch from my watering frequently and leaving the soil damp enough? I don't know, not a bug or plant expert. But what worked for me was two things. To kill the existing bugs (but not damage my plants too much) I made a bug spray out of a compilation of diy recipes I found online (soapy water, bit of vinegar, and then letting some crushed/ground chili peppers and garlic cloves "ferment". Used that to kill the ones I could find. I also switched to using a self-watering tube that delivered water below the surface (a ceramic tube that gets pushed into the soil with a tube that runs to a bowl/jug of water that I keep next to the plants). Bug-free now, so long as I keep the soil surface dry.

I have no idea if this works yet but I just got some recycled glass bits to put on top of the soil--like a decorative mulch I guess.

I was unable to grow certain plants due to fungus gnats, but other plants did just fine. No matter what, my rosemary, thyme, and bird's nest fern would teem with them. I bought a spray from Whole Foods (ironically made with rosemary) that's specifically made for indoor plant pests, but it seemed to harm the plants just as much as the critters.

A philodendron, corn plant, angel's tears, and a variety of succulents occasionally get a gnat or two, but have thrived.

I also had this problem and the guy at the nursery told me to re-pot my plants because the gnats (flies) are in the soil--that's where they lay their eggs! Gross.
After re-potting, they are gone. Also do not over water your plants which encourages the gnats arrival.

the coffe grounds work as repelent

Thanks for all the good advise. Last year when I had to bring all my plants inside due to the cold weather there was just a congregation of gnats. I used the sticky tape traps and they worked really well but they sure are unsightly and I do use insecticide soap for aphids but not for gnats.

Thanks for so many great tips here, all! I have a gnat-infested snake plant in my living room that I'm going to try one or two of these ideas on.

Hey guys, I fought a huge fungus gnat invasion a few years back and thought I'd share what I'd learned.

Fungus gnats don't eat roots, or the plant at all; they are just there to lay eggs in the wet soil. So they only really harm very young plants, or plants that have root damage already.

Fungus gnats can only live in your soil if you have super saturated soil. That can be a product of over-watering (let the top soil dry out between waterings, and then water deeply through a bottom saucer), or a product of compacted, poorly drained soil (you're watering right, but your pot has no drainage so the bottom soil is always wet. This also risks root-rot, and the root rot might be what was actually killing your plants rather than the gnats).

The best way to get rid of fungus gnats to use a decent insecticide (there are several organic ones targeting gnats directly) dry the soil out completely, and leave it dry for a day or two, so their life cycle gets broken. The problem there however, is if your plant isn't terribly resilient. I don't think I would use the moth ball approach...there's just too much weird stuff in those that the plant could soak up and store, even if it doesn't harm the plant outright.

Fungus Gnats suck, the annoying little boogers. I hope this helps you get rid of em, or prevent them next year. Good luck!

nematodes

Bowl of soapy water next to my plants takes care of the problem.

Apple cider vinegar works well for fruit flies, but for gnats carried in on outdoor plants we had a lot of success using sand. Put an inch or more of sand on the exposed soil to prevent eggs from being laid and avoid over watering. When the gnats die cycle out the sand and soil. Good luck!

A number of people have pointed out that the problem is with fungus in the soil, and the gnats like the fungus. But nobody has a solution for getting rid of the fungus, aside from getting rid of all the soil.

Your plant has been innoculated with the fungus. It will not go away. Ever. And your watering habits (like mine) are encouraging it to grow.

Fungus in the soil is not bad, per se, except when it's not balanced by soil bacteria. Given the sterile stuff we usually plant our plants in, or the chemicals we spray on after, it's probably missing or underrepresented.

Amending your potting soil with worm castings would help. Compost tea, too, if you have a source. The simplest thing to do to make your plants happier, though, is to dissolve a couple teaspoons of black strap molasses into your watering can (I use a cup of hot water for this). In addition to providing micronutrients, the sugar helps kick start the bacteria in the soil.

You all are incredible. I'm starting at the top & working down until the gnats are gone!

Thank you!

Any luck with the gnat war?

I've had my best success with sticky traps for the adults, and gnatrol (I think) in the water. Look for a product with Bti, not just Bt.

Most fun weapon in the arsenal: one of those electrified tennis racket zappers, really meant for flies and such, but so satisfying to get those gnats that just keep weebling around.

Love all of the ideas. My husband and I are going nuts with these little critters! Can't wait to try all of these suggestions, thanks for the help!

These things were drivinhg me nuts. I took drastic measures but it's worked so far.

1) Let you plants dry out. Cover toilets, drains, dry off sinks, etc. LEAVE NO WATER.
2) Get yourself a mask some latex gloves a rag and a can of Raid Ant & Roach Killer.
3) Take your plants, sausers and coasters outside.
4) Put your gloves and mask on.
6) Spray your coasters, sausers, plants, soils & pots - tops, bottoms, inside & out with Raid so that you get all areas & leave everything outside overnight or longer if you can.
7) Spray all your outside plants as well if you have the same problem, especially in the area where you are spraying your house plants so they don't spread.
8) Open some windows throughout the house & turn your ceiling fans or kitchen fan on
9) Spray your rag with Raid outside, go back inside, wipe the surfaces with your Raid rag in the area where your plants sit (cover the area like you would when wiping a counter off, not heavy like dusting. It doesn't need to be soaked). Wipe off the excess with a dry rag.
10) Go back outside before you take off your mask & leave your rags, mask & gloves outside & leave your house for the day. Leave some ventilation in your home that night.
11) When your plants no longer reek of Raid bring them back inside.

Day one a few were still flying around, maybe newly hatched. Day 2 I killed a couple more. Yesterday I saw one. Today none.

Glad to know I'm not the only one experiencing this!!! They're driving me absolutely CRAZY!! ...Replanting is not an option, the pots are MASSIVE and can't be moved. Took 9 large bags of soil each pot. .... So, I plan to try everyone's suggestions i.e. dry out soil, prepare dishes of soap and purchase a can of Raid. Such a pain!! Anyway, thanks everyone for your suggestions. fingers crossed!!!

Try misting a combination of geranium oil (I use DOTERRA) and water on your plants and in the soil. This will not harm your plants. The gnats will hate the oil and will disappear. Spider mites and other bugs will also stay away from indoor and outdoor potted plants.

I got so upset with them,I bought a can of Raid flying insect spray.Went all over the house spraying like I was using Housespray all through the plants and everything. I'm scared to water them now. Because I been living in so much peace without the gnats.

Wow... glad I am not the only one fighting these pesky little critters. I did the whole repot, clean the plant, new soil thing and I am still fighting them. The soil is dry in all my pots. Going to try the coffee grounds next. These plants are on their way out the door next... :(

All these suggestions are great, however, re-potting 53 house plant's (last count anyway) is out of the question because I have so many, most are pretty big, like my money tree, it stands over five feet tall and the thing is so touchy, I don't want to kill it.. I don't have this problem in all plant's, but finding the exact one is craziness. Those things are so small, but annoying and always seems to land in my coffee. I'm going to try the coffee grounds trick, along with the potatoes and vinegar. I'm not going to water for a bit and I'm going around and turning the dirt in all the plants first. You guys are great and I'm glad I'm not alone. I do know how I got them though, it was a bag of potting soil I bought from Home Depot and the chick there, said to just let the dirt dry out and it would be fine. It wasnt and I brought the remainder back. GGGRRRR Now I open the bags in the parking lot. :D

There are so many great ideas here!I've been fighting what seems like an endless uphill battle for so long.
I have a large collection of plants at work and my house. I'm fairly certain my plants picked up the gnats in my office and subsequently my home when I took some to be repotted. I should be able to get my house under control now, but I worry about the plants back at the office.. I work in a very large, open building and more than 50% of my colleagues have plants. So obviously I can't eliminate the gnat epidemic on my own there, but I can't stand being under constant attack for much longer without having some sort of breakdown. What would you suggest I do to keep the gnats from taking over my cubicle? I realize its probably going to be something I must attend to on a regular basis but I'm desperate enough to do anything!

I'd be willing to re-pot my plants but I'm wondering, is it possible that the eggs could be in the soil - like in the bag of soil I have?

Put sand on top of the soil in your plants they dont like sand.

put sand on top of the soil

We recently brought our fern in for the winter. About a week later, I noticed a little fruit fly looking critter doing a fly by while watching a movie; killed it and carried on. After getting back from Thanksgiving vacation, I noticed a few more and my wife told me she had seen some near the plant soil. I wasn't overly concerned. Today, I notice in my plant aquarium (fish tank for plants without fish) that there are little inch worm larva looking things swimming around and then notice a few gnats on the water. YIKES!
We brought in gnats with the plant and they are spreading. Solution: kill the gnats from the plant with Ortho Elementals Insecticidal Soap that I use to keep grubs from eating plants and add guppies to the plant aquarium.
I will let you know how this works out for us.

HOW I GOT RID OF THE PESKY LITTLE BU

HOW I GOT RID OF THOSE PESKY GNATS IN MY HOME

A month ago I desperately went online to find a way to get rid of those pesky gnats. They were literally driving my family crazy. I don’t know if there is a difference between fruit flies and gnats but I normally have a few fruit flies due to the fresh fruits I normally keep on my kitchen counter. About a month ago I decided to liven up my home by including a few house plants in my living room. My God! We were bombarded with Gnats. Nothing I have ever encountered before. They were everywhere, in my bedrooms, bathrooms, kitchen, dining room, and food pantry. My children were very annoyed and wanted me to get rid of the plants, my babies. I went online to look for a remedy. From all the bits of information I acquired I decided to create my own remedy, (my ten easy steps). IT WORKED!!! Within a week I was rid of those pesky little buggers. It may seem like a lot to do but it’s worth trying.

Ten Easy Steps To Get Rid Of Gnats In Your Home:
1. Take plants outside
2. Carefully remove the top layer of soil and any dried leaves from plants
3. Mix a combination of 1 tsp vinegar and a pea size of soap in a small spray bottle of water (use judgment)
4. Spray entire pot, plants, and soil with vinegar and soap mixture
5. Use dry rag to clean off the exposed inside and outside of pot
6. Add fresh soil to pot to replace the top layer you removed
7. Cover top layer soil with aquarium pebbles (I used the brown ones to give it a natural look. Sold at Wal-Mart or pet store)
8. Water plants at the roots (avoid overwatering)
9. Spray entire plant and soil with Fungicide 3 (Fungicide 3 sold at Wal-Mart)
10. Use Fungicide 3 spray to kill gnats left inside your home (fungicide 3 is safe to use inside and outside your home)

Note: The soap and vinegar will help kill the gnats and their nest eggs from soil and plants. By cleaning the pot with rag after spraying with vinegar and soap mixture will also help remove any powdery mildew that are typical in houseplants pots. Mildew are dangerous not only to the plants but to our health as well. The aquarium pebbles will help to keep the top layer of soil dry and also keep pesky bugs and fungus from living, hatching, and growing in the damp soil. The Fungicide 3 is organic and is safe to use on inside and outside plants to control black spot, rust, and powdery mildew. It also controls other insects and spider mites from inside and around your home. DON’T FORGET TO BRING YOUR PLANTS BACK INSIDE.

neverheidae, I have bought and tried a few insecticides without any luck. Would you be willing to tell me the name of the "organic ones targeting gnats directly" that you used? Don't want to waste any more money on ones that don't work. Thank you so much for your help.

You know what..? I'm posting a comment merely to vent my frustration!!! Because I am SO beyond annoyed with these itty-bitty buggers!!!

Since I moved into my new house, my normally, very healthy, three year old had been sick constantly and I was desperate to find some kind of resolution to improve the overall air quality of the home that is a little older than what we are used to living in (theorizing that improving the air quality might help his immune system fight off viruses).. So I read about the NASA survey's 10 plants that have proven air filtration qualities and I went to Home Depot in October 2012 and THOROUGHLY inspected every single plant I was purchasing for spider mites, and any other inconvenient stowaways.. I bought an English Ivy, Rubber Plant, and two Peace Lilies - NEW organic soil and pots..

The Ivy was the first one to bite the dust.. Apparently I missed the Spider Mites in the initial inspection. I changed out the soil 3 times and gave up and let it die.. Outside. It didn't take long.

Then the rubber plant had the gnats. I sprayed it repeatedly with vinegar and soap solution to no avail. I eventually left it outside and forgotten about it over the ONE night it froze outside.

NOW.. My Croton plant (that I also battled nasty critters with initially and brought it back to life), and BOTH peace lilies are harboring the gnats. I'm so freaking frustrated!! I spray and spray with soapy water - which kills some initially - but they always manage to come back!! And its hard when your husband works seven days a week, with a 3 year old, to have the time to sterilize, pots, and dirt... I'm thisclose to seriously giving up and buying a air filtration system.

Gnats! It is painful to read these posts for two reasons. One, what should be a fun hobby is being destroyed by these pesky little critters. Though they pose no harm to established and healthy plants, they are a nuisance. Two, the disastrous lengths that everyone is posting to rid themselves of these pests. I am in no way meaning to offend ANYONE (disclaimer). Applying chemicals to plants is a horrible idea. Raid is the worst thing to spray on a plant, especially in an organic soil. Insecticidal soap is also full of antibacterials, not good for the life of the soil. Baking your soil? Wouldn't dream of doing that again, Been there done that, cooking kidneys and liver smells better.

There is a product called neem cake available from www.neemresource.com. It can not be replaced with neem oil, neem oil is to be used as a foliar spray. This neem cake is mixed with diatomaceous earth (a product purchased at an auto parts store used for oil absorption, not montmorillonite clay). This neem cake and diatomaceous earth(DE) mix is used as a top dressing for the plants. The DE actslike razor blades to the gnats AND larvae, killing the whole herd. The neem cake is an ALL NATURAL AND ORGANIC byproduct of making neem oil. It has natural insect repelling properties that keep gnats and grubs and spider mites, etc. away. This DE and neem top dressing will keep you gnat free. Also, the neem is rich with nitrogen, fertilizing the plants as well. Thank you

I actually read on another site to spread 1/2 inch layer of sand on top of the soil, so I did... and on top of my plants looking very zen, (some small rocks are mixed in with the sand so it looks cool), they are now completely pesk free!!!!

In how much water?

Interesting thread. I never had these until I bought 3 herb plants and a bag of container potting soil from Home Depot last month. Now it's crazy in here with little flying critters! I started spraying with soapy water (watered down Simply Green). This container potting soil is designed to retain moisture, so I may have to change the soil or mix in something to help the drainage. What a mess! Doesn't look like my other plants are infected yet. They have icky old dries-out-like-crazy soil, so I guess that's good in this case.

I have read much today and can share some things with all of you. I found mushrooms first coming up in my house plants so, I investigated that cause. Thinking that I had added only 2 things to my potting soil, ( coffee grounds and washed out eggs shells for the nitrous) that may have caused the fungus I blamed it on my self. The fungus was from the potting soil. I can tell you this because I never added either to the bag that sat outside my door of my apartment. The fungus did come in the bad that I bought from a store. I can tell you this because I looked inside the bag and the mushrooms (fungus was in there).
I remember the idea of trapping slugs (beer in a cap) so, I'm going to get the sweat vinegar and work from there. Hope to show some improvements quickly because they are BITING ME !!!!!

Just to know I am not the only one dealing with the annoying issue of plant gnat is a huge relief! Thank you all for my Gnat-therapy!! I am a plant lover and cannot imagine living in a plant-less apartment so getting rid of them is not an option. Well, Spring sprung and so my task of re potting my plants and welcoming new ones to my apartment. Diligently, I went to HOME DEPOT to purchase my gardening supplies. After reading some comments I am confident the soil was the issue and what started it all!! I will try the coffee grinds and vinegar first since I have plenty at home. Hopefully this will suffice but if not, I will go down the list. Note to self, never ever buy dirt at Home Depot. Cheers to a hopefully Gnat-free Summer!!