I love indoor plants but hate the gnats. I tried all these natural, stuff you have in your cupboard stuff. The first thing was H202 ( hydrogen peroxide). I mixed it with water, I poured it full strength into the soil, I set out bowls. Nope. Not effective. I used a spray bottle of straight rubbing alcohol. It didn't hurt the plants and there was a certain satisfaction in seeing the gnats try to swim out of the liquid. It only works on the surface though. I put a layer of sand 1" deep over all the soil in every pot. Nope. I tried "earth" (Diamateous powder). Nope.So one day I got to thinking. How do floral shops and garden centers keep fungus gnats away? I googled it and came up with nematodes. They eat the fungus gnat larvae. Hmm. So I bought this stuff. By this time I had tossed out a few plants that were looking sickly due to the gnats so the infestation wasn't as bad. But still there is nothing more annoying than a single gnat flying around your head and landing in your nose. I noticed that one plant had a couple of gnats flying on the surface so I put some nematode stuff into the top of the soil and watered the plant. For a week afterward if I saw a gnat I would hunt down the plant it was after and do the same process. I re-potted some plants and mixed just a little in the soil. It's been about two weeks and I seem to have won the battle. This nematode stuff is a miracle.

UPDATE: These nematodes worked at first but unfortunately after a couple of weeks the fungus gnats were back so clearly they did not have enough nematodes to eat all the fungus gnat larvae. I followed the instructions to the letter. I had two packs on one plant which has a pot that is about 8 inches in diameter and one pack each on my three other plants which have pots that are 5 inches in diameter. The plants are all in the same room and are the only plants in the house and they reside in a room in which the door is always shut. I did two applications, 5 days apart, making sure to give them a little water each day to keep them moist. In between the applications I had the nematodes stored in the refrigerator (as you're supposed to do). I've had to place an order for Scanmask Beneficial Nematodes, which I've used twice previously and in those cases the fungus gnat problem was eradicated quickly and permanently. These were cheaper and I have such a small amount of soil that needs to be treated so I figured I would try these. Too bad it ended up being a waste of money.ORIGINAL REVIEW:I bought a few indoor house plants recently and they were infested with fungus gnats. I put one pack of the beneficial nematodes on each plant and watered the packet and the fungus gnats were gone within two days. I tried to kill as many as I could see flying around after installing the packets. I picked the packets up off of the soil after 5 days and noticed the packets were empty so clearly the nematodes migrate from the packet into the soil after being watered.I had purchased beneficial nematodes twice previously from Amazon many years ago and they came in a Styrofoam cup mixed in with soil. The advantage of having them shipped in soil is you can spread them over many more plants. For my purposes, the nematodes in these little packets packaged inside of a plastic "egg" was convenient as I only had four plants that needed attention. If you have more plants you will probably want to find nematodes that are shipped in a container with soil so you can apply a small amount to each plant. The nematodes are very efficient and really wipe out the fungus gnat larvae quickly as long as they're alive when you get them.

Since the reviews here are iffy and there are no easy better alternatives to these on Amazon, here is my review. Upon buying, you will get some pouches, which you need to put near at the top of the soil (in terrarium pots in my case) where there is space, next to your plant(s) that is suffering from gnats. I had 2 indoor open terrariums that had gnats, which kept multiplying, hence bought these to see if I could rid them.First, delivery was awesome, came on a Sunday morning without extra delivery fees.First 3-4 days: It will not be obvious to you at first if these pouches are making a difference. I couldn't see any of the nematodes and it was not obvious whether the little balls inside the pouches were the nematodes and, if so, how they are going to work.1.5 weeks: I noticed that there were noticeably fewer (maybe 30% less?) gnats in my 2 terrariums. Since the gnats had previously multiplied at a rate that was noticeable every 3 or so days, I thought maybe the nematodes were working. The pouches didn't change in appearance. You are supposed to keep them damp, which I did.After a whole 2 weeks or so from applying these pouches: - In 1 terrarium (with 2 tiny plants inside), the gnats were gone! Amazing since that terrarium had been suffering from gnats for at least a month and my plants had visibly lost vigor due to those lousy insects.- in the other terrarium, there were no gnats flying about, though upon looking closely there was a few still inside on the soil. This was a big improvement since for that one, I had been killing around 7-20 gnats PER NIGHT before the pouches came.- I still had a good number of pouches left, which you are supposed to keep at a certain temperature range. Since I was worried that the pouches were too cold to keep in my frig but normal temperature in my house was too warm to keep these pouches "effective" long term, I decided to use up the remaining pouches on my (cilantro) plants outside on my deck that had gnats.- overall conclusion: these nematodes work. After they are done, you will know because the little balls look "dried up" (as opposed to moist balls). These nematodes do not move or look like animals at all, so you may wonder what the heck it was that you bought. However, it was clear they were effective because my gnats were gone and they did not just disappear by themselves. You just have to be patient; they will not work overnight but will need about 5-10 days. Be sure to keep the pouches moist.Last word: my terrarium that was especially previously gnat-infested became 95% gnat-free, but my plant never recovered, so after about another 3 weeks (in addition to 2 weeks w/ these pouches), I decided to give up on the wilted plant and put a new plant, with new soil, in the terrarium. So, lesson learned is to try to not have overly watered plants in the first place, otherwise curing becomes bothersome or not effective regardless.