GREETINGS AMIGOS, today I am going to help you tackle those pesky Fungus Gnats that invariably inhabit any all-natural growing space from time to time; normally in small numbers, but sometimes they get out of hand and get crazy! I’ll dispel some bullshit regarding these little buggers and help you to keep them in check using simple all-natural methods mostly, but a little flypaper doesn’t hurt either, and it’s basically harmless, heh heh. Read on Earthlings, and welcome to: Fungus Gnat Warz!
FYI the aluminum foil on the window is actually heat insulation from direct sunlight outside. This works well and changed my temp by 8 degrees in this room. From the outside you only see black (card stock) and I would tend to advise anyone against having their windows be covered with aluminum foil so that the foil was seen from the outside—too many implications there—wink.
Let me start out by telling you all a little bit about my indoor personal home cannabis garden. Right off the bat you need to wrap your melon around the fact that you will have some fungus gnats in any healthy all-natural garden, period—otherwise it wouldn’t be supernatural—life happens. So, get any thoughts of genocide of them out of your head right now. I use an extra bedroom as my flowering room with a couple grow tents and a sprouting closet, and I also have a couple of tents, two cloners, and an open veg zone in another bedroom as well. In my flowering room I also run a small indoor worm farm; so, as you can well imagine I have some experience with the gnat invasions from hell—think about running a worm farm in other locations as well.
NOTE: You can easily run a worm farm like mine in a shed or garage, or hell man, even in a camping type tent outside. As long as it has some ventilation, doesn’t get roasting hot or hard freezing cold; no direct sunlight, and totally protected from rain.
Nitrogen near the surface of your growing containers’ soil-mix, and especially manure that is high in nitrogen there, will serve Fungus Gnats well; and their populations will absolutely BOOM if you do something like top dress with manure high in nitrogen and organic matter. So, keep that in mind as well, as we proceed into this article and you can use this knowledge as a preventative measure in particularly gnat prone environments. Let’s rock and roll homeskillets…
Rev’s Tip: If you run an indoor worm farm like I do in my garden space, use DE right on the lid to help control gnat populations that may love your worm farm. Stop using any kind of manure in your worm farm if you use it, because the gnats will get way out of control fast with a manure source.
Don’t Freak Out, Seriously…
I have heard many peeps try and tell me the “horrors” that fungus gnats bring with them into your garden, things like diseases/viruses and pathogenic microlife in general, essentially because they read it from someplace, someplace motivated to shoot some fear into peeps, because fear sells man, ya gotta “kill everything now” … according to them—heh heh. So, let’s break all that down into a few parts, according to me and my experience.
First of all: Is it possible for fungus gnats to bring disease into your all natural TLO indoor garden? Absolutely, that is true and it is possible; however, it is highly unlikely as long as a few basic rules are followed. Fungus Gnats born and raised in your garden indoors harbor no disease or pathogens unless they came into contact with those bad things somewhere already in your garden. Cheap soil, manure, top soil, compost, and even mulch sometimes, can bring in Fungus Gnats with them. So, make sure you dial these sources in and it’s best for sure to recycle your soil for this reason and many (many) more. So, the risk lessens if you aren’t bringing them in with a cheap/sub-par bagged soil or soil amendment. It’s possible I will be hit by lightning too, but like Fungus Gnats bringing doom to my garden, it just isn’t likely unless they are imported.
Second point: Please do not have a knee-jerk reaction to run out and buy some kind of poison to kill all these “evil” little flying gnat buggers; Peeps trained by advertising/commercials, listening to “the hydro-shop guy” for example, and Liquid Synthetic Nutrient corporations tell you that you have to do that. Anyways, you NEVER need to use poison in my experience to handle gnats. Their larva form in the soil does not harm your roots as long as you are growing in healthy living soil; however, in a synthetic soilless garden, since the roots are the only organic food source present, they can and do harm the roots by feeding on the root hairs. So, they are a big problem in that situation.
Final point: You should always pay special attention whenever you bring inside anything from outdoors—like compost in a pile outside for example—into your indoor garden. High probabilities you would bring in some Fungus Gnats (along with a whole bunch of good microlife). So just make sure the compost pile is a healthy one full of life, and odds are everything will be fine. Don’t trust compost you aren’t sure of, because outdoors things are tougher, and you don’t want to bring in any extra tough bad guys from some funky compost pile. Make your own, it’s easy.
Rev’s Tip: Remember my Supernatural friends, in a healthy happy indoor TLO garden you WILL have at least a few Fungus Gnats buzzing here and there, so you need to adapt to that right off the bat if it freaks you out. If they get out of control it will take several days to knock them down, staying poison free—so let’s do that, yeah?
Using Diatomaceous Earth (DE) Effectively
Diatomaceous Earth (DE) is incredibly effective against Fungus Gnats when used properly, and make sure it is ONLY DE (100% DE) and NOTHING else. Do not use pool filter grade DE as it will not work at all and may also be packing some toxic crap—highly likely. I recommend food grade DE and it is well worth a couple extra bucks to make that happen, in my opinion. But pure DE for garden use is all good too, as long as it is pure DE—read the label carefully. In the photo you can see my DE manual squeeze ball blower and this is the best and most effective way I have found to apply it to the top of the soil in my containers. You waste very little this way, and you just need to get the hang of using it, but it’s easy. Just practice a little outside first with it, heh heh. The actual DE blower is called: B&G Bulb Dust-R Model M1150 and I got mine on Amazon, but there are many styles available and a good nursery should carry them as well, I think.
NOTE: That DE Blower in the photo also works very well as a pollen blower—FYI
What DE is and how it Works
DE is little tiny itsy-bitsy skeletons from fresh and salt water dwelling microbeasties (hard shelled algae). These little skeletons are like razor wire to little larva exactly the size of Fungus Gnat larva and they cannot deal with it, then it kills them. Slicing them to death is what happens as per my understanding; quite a yikes way to go, but nature’s way is harsh at times. It also will hurt but not kill adult flying gnats who tread upon the DE. DE also packs a nice little dosage of silicon (Si) which is awesome, as it is a primary nutrient used by the plants (and certainly some by soil life) which is fairly exotic to find in nature in these ratios, I believe; and when it breaks down in the soil it feeds all the life including the plants with Si and calcium. Along with the razor wire effect, it will also hyper-dehydrate small insects, arthropods, and larva, so it is a double-edged killing sword.
Just make sure the DE you get has not been heat treated and is food or garden grade and 100% DE and you should be all good; now, let’s talk about how DE doesn’t work. You want it to stay dry, so after your top layer of mulch is dry on your container plants, you apply the DE with a blower like mine, or you can just sprinkle it on; just make sure it stays as fluffed as possible throughout applying it this way. Once water or moisture hit the DE it becomes less effective and looses its razor-sharp edges, due to it starting to be decomposed. In very humid environments it is less effective for this very reason.
So, applying DE to your containers over the course of about a week in this manner is the plan, only when the top layer has dried out, and after you water the next time, just do it all over again and reapply when dry. Let’s do this right, so here’s another good method to use for that same week you are applying DE, and in concert these two strategies kick gnat ass…
This is super easy and self explanatory for the greater part. If you are using those self watering style containers this is truly simple to do. While using the DE on the surface of the soil as explained previously and being able to bottom water effectively works amazingly well. In order to do this using normal growing containers/pots you will need to have catch trays underneath your pots and you simply water the plants for that week by filling the catch trays and letting the plants take the water up. Just make sure the catch tray holds enough water to provide the plant enough hydration per watering, and NEVER let the trays hold standing water for longer than 30-40 minutes before sucking the extra water out—a turkey baster works awesome here for a home garden for this purpose—because standing water for too long will drown roots and invite problems.
NOTE: Since the larva form of the gnats live in the top couple inches of soil-mix the bottom watering will also really create some extra havoc for them with some extra drying out/dehydration up top.
Extra Gnat Punches
Having some decent air movement (using small fans) along with some of those fly-paper sticky traps in combination with everything else pretty much seals the deal on the gnats and their numbers will fall off within 5 or 7 days; and within 10 days or so they should be down to minimal once again. The flying versions of these gnats really hate air movement as they are not powerful fliers. In their larva stage living in the top couple inches of the soil-mix the gnats actually do a decent amount of good by aerating the soil-mix (via tunneling through it constantly) and processing organic matter like all the other good micro and minibeasties in an all-natural soil-mix. Rock on mis amigos, try it, it works!