Sciarid Fly Killer Nematodes 15 sqm

This review is in 3 parts: 1st is this product (effectiveness, product use and conclusion). 2nd is general info about fungus gnat. 3rd part is on alternatives to nematodes that I know about.This product:Effectiveness:I wavered between 4 and 5 stars - they were not 100% effective for me, but worked quite well compared to other available products, although found it quite time-consuming to apply. I had already used BTi multiple times, and Hypoaspis miles mites once (think I spelt that correctly), so not totally sure which worked, and none of it worked 100%. I had a really bad infestation, about the worst I've had, and I've had a few. Initially, the mites seemed to do nothing, but I waited about 10 days after using them before I used the nematodes. 72 hours after the nematodes, I still had a good number of adult fungus gnats flying around, although there was a noticeable reduction. At around day 4 - 5, they were nearly all gone, but as I don't remember nematodes taking that long to work, not sure if it was the nematodes, but tend to think so.. But nothing I've used has ever worked 100% with 1 application so far. I know some reviewers said they totally got rid of them with this, but I didn't, and I followed the instructions carefully.Product use:As per other reviewers, you have to use all the product within a short time frame (mine had an expiry date about 3 weeks after delivery), and store in the fridge until use. You receive a white-ish powder, mine was slightly moist, which you use to make up a concentrated stock solution, then dilute this in several portions to apply, and you are told to use up all stock solution immediately, as it doesn't store. You are advised to use a watering can with a coarse rose, or a hose end applicator. I just used a normal watering can without a rose, but made sure I thoroughly and evenly drenched the compost. You can use it more concentrated, if you've got more than you need, as it can't be overdosed - you just pay for more than you need. I've found both times I've applied nematodes that I ended up with too little stock solution for the last batch, despite careful measuring. As I had more than I needed anyway, this didn't matter, but also found that you need to stir both the stock solution and the diluted solution more or less constantly, or it settles to the bottom. I found it quite time consuming to apply because of this, and because I was applying to lots of little pots. The last batch, I applied nearly pure concentrated stock solution, hardly diluted, and made sure I stirred it every 2-3 pots, and drenched the growing medium evenly right through. Despite this, it didn't kill all the fungus gnats where I had the highest numbers, and while most were gone at day 5, it only takes a few and they proliferate again.. The soil also needs to be moist before you apply, so you easily end up over-watering by the time you've drenched the soil with the solution - some of my seedlings died from over-watering rather than the fungus gnats.. But that's because I was using it on young seedlings, some not yet germinated, which don't need regular watering yet and are highly sensitive to overly wet compost, too. It says to apply on a dull day or in the evening, as with all nematodes.Conclusion:However, I think it did kill all larvae in most pots and most larvae in worst affected areas (I had a few propagators that were literally crawling with them). So decided on 5 stars.. Overall, while this is more effective than BTi or mites, you will possibly need more than one application, depending on how severe your infestation, what type of growing medium you use, soil temperatures (needs to over 10 C), how well you distribute the nematodes (stirring, drenching well) etc. Compared to the other options on the market (see below) would recommend this for more severe infestations, if you're prepared for the fact that the 1st application might not be 100% effective.General info on fungus gnats:They are small black flies, that run over the top of the compost when disturbed (at watering, especially) and lay their eggs in the top soil layer. The larvae are small, but visible to the naked eye, white with a black head and live in the top soil layer. They mainly eat fungus (hence the name) but the larvae also eat tender plant roots. With mature plants, usually, only long-term, severe infestation will cause problems, but they can kill young plants or seedlings and they spread diseases amongst plants (and the adults are annoying, although harmless). For me, the only thing that works completely is to avoid infested compost, which is hard. It is often stated that fungus gnats come from over-watering, but that's not true, in my experience, and have read nursery studies which confirmed this: fungus gnats like moderately moist growing medium, just like plants do, neither too wet or too dry. So I would ignore the advice on the packet about less watering to prevent future infestation - it's a myth. You get fungus gnats when you import the encapsulated eggs within compost/new plants, or less frequently, adults or larvae. As many compost bags have holes in them, and many suppliers seem to store it outdoors, even good quality, expensive compost can contain them. The problem is also that the eggs are dormant and encapsulated until they encounter good conditions, so until you use the compost and water it. They can survive almost total drying out and low temperatures while dormant, so you don't know you've got them until too late.Alternative remedies:All are expensive and not very effective, as said above. These are the ones I've used:Bacterius Thuringiengsis Isrealis - the last bit is important, there are multiple different types of BT, and you need the one usually sold for killing mosquito larvae. You can get solid product (mosquito dunks) which you can either dissolve in water or apply to the top of the compost dry and water in. There are also water-soluble versions especially for fungus gnats (Gnatrol etc), but nothing available easily in the UK - usually, you need to import this from US, since Gnat Off was discontinued (sadly).There are different types of predatory, live mites sold that eat the larvae. Both these products have disadvantages: the mites work slowly and are not suitable for heavy infestations (didn't realise that initially) and are temperature sensitive, at least the type I used are. The BTi works quite quickly, but may need multiple applications, best every few days - effectiveness seems to vary widely: sometimes, 1 use kills em all, other times, you need 3 or more.There is a liquid product called Nilnat or Tanlin, which I've used in the past, not sure what's in it, as it doesn't say. It is expensive, although lasts forever, as you only need a few drops, but I've not found it very effective myself.Not sure about the Nilnat, but the BTi, nematodes and mites can all be used together without negatively affecting each other.There are various things you can spread on the top of compost: sharp sand, aqua clay balls, or there are dedicated products, but in my experience, this is more suitable as a preventative measure. Although if you use infected compost beneath, the flies will get out, just not as many.Coffee is also supposed to kill the larvae, and before I buy another packet of these, I might well try that, as cheap and easy..You can also use yellow sticky traps to help control (and monitor) the adult flies (the other products only work on the larvae and do not kill the adults or the eggs, maybe that's why it took so long for the nematodes to work, because the eggs all had to hatch first).You can also vacuum up the adults, as they don't fly very well, in addition to measures that kill the larvae.Sorry, long review, but thought I'd share what I've learnt in my most recent battle.

I use this product once a year as the flies start to appear in the house as it warms up. It has always worked but be aware that if you bring a new plant into the house which hasn't been treated, you may well get a return of the bugs.

Delivery very prompt, good instructions, just hope ir works to kill these root fly larvae.

Gnat flies...I had tried everything to eliminate them, or at least keep them at bay. I managed mostly with various methods that I won't bore you with, but a few always seemed to survive no matter what. I don't mind "some" providing they don't damage my plants (and those sticky yellow things you can buy help as well.) But the problem was getting worse - or rather I was getting lazy in keeping their numbers down.I had no idea what Nematodes were, and it was only when I was exploring new methods online of controlling them - that I came across the suggestion to use them to destroy those pesty erm...pests. I don't know how I didn't know about Nematodes before, but I wish that I had, as I've had huge success with them. I used the entire packet to treat nine house plants, with the volume of water I used making the solution somewhat more concentrated. But the instructions said that was ok... and I had a lot of Gnat flies, so I didn't want those Nematodes to feel out numbered.While they have worked very well (with one exception that I'll come on to later), I did deviate from the instructions provided a bit. Firstly, I used slightly warm water to make my solution and to water my plants. The instructions didn't state to use cold or warm water. My reasoning for using the latter, is that your soil temperature needs to be at least 10-degrees. Adding cold water would surely make that plummet down - especially if you are planning on using this in the cooler months. I also treated my plants during the daytime, and left all the pots on the windowsills to keep that soil warm.I decided to submerge my pots in the solution and let them sit for a minute. Essentially I made my Nematodes solution in a bucket, then dunked each plant pot one by one. You might not want to do it this way if your soil is waterlogged already (or doesn't drain well), or if you have some very water hating plants (like my African Spear Plant). I also had neglected to water my plants for a while before using this solution, to let the soil dry out as much as possible and so plants weren't sitting in water for even longer than needed.The only plant I didn't treat this way was my African Spear Plant. Because of that plants root and rhizome structure, they can and like to go without water for a long time. I watered this plant from the top with as little volume as I dared. That plant still has a some flies which could be down to my lack of confidence in soaking it with Nematodes or the plant itself. Thankfully my ASP can sit without water for a few months now, so I hope the soil will be so dry that any larvae will die anyway.My experience is based on my houseplants and such, so you might want to follow the instructions provided 100% or follow what worked for me (or a bit of both). Either way I think and hope that these Nematodes (which by the way I'm pronouncing KNEE/MAT/TOADS with no idea if that is right or not) will work as well for you...

We had been battling fungus gnats for over 6 months. Mosquito bits/ dunks (TBI) didn't work - arguably it even made things worse for one of our plants because we had to keep watering to apply the bits. The yellow sticky traps were full and we would usually see 5+ fungus gnats everyday on the walls which the traps weren't working against.After applying nematodes following the instructions (extremely concentrated dose as we don't have that many plants - you can't overdose), we felt there was no effect until about 10 days later when we noticed for the first time in 6+ months no fungus gnats flying around. We've noticed 2 gnats in the last 3 weeks which is virtually a complete elimination of gnats since pre-application of nematodes. Very grateful to the sellers of this product.

Bought to reduce a fungus gnat infestation affecting 10 indoor plants - was plenty to go around them. So this was used to kill the larvae and I added diatomaceous earth to the top of the pots once soil had dried out. Both products I believe worked very well to kill the larvae and adults Fingers crossed it is a permanent fix! Good price.

Followed the instructions exactly and treated all the plants as outlined. Still inundated with flies weeks later with no sign of them reducing. Didn't work.

This product worked. However, i preferred it in a tub, as it was packaged last time as struggled to empty out the contents from the plastic bag it arrived in.