Loading... Please wait...

Having a black fly - fungus gnat problem? Problem solved!

Posted by

Many gardeners amongst you keep telling me about the lengths you all take in regards to cleanliness and hygiene, when it comes down to creating your grow area.

You have sterilised well, made sure that everything is clean, re-cleaned and inspected, and re-cleaned again. (I know one mate of mine who even wears a white overcoat; said it was an extra preventative measure. But I think he just likes playing mad scientist lol)
so you enter you’re grow room or unzip your tent and... OMG! Shock, horror, or the most commonly screamed out term is "what the f***....why?" You see, it’s an initial shock to most indoor growers when they enter to find a swarm of little black flies hovering around the stems of your girls.

Aaaaarrrggghhhhhh!!!!



Well my friends, quite simply, you have Gnats (also known as fungus gnats). These little pests are not as bad as they look BUT anything that may hinder my girls is a no no. The larvae of fungus gnats feed on plant roots and fungi, thus ANYTHING that’s going to mess with my root zone is well and truly out of there!

Well nature is actually “mother nature”, and she certainly is definitely not someone to mess with, your best form of approach with her is to ever so gently nudge and guide her as required BUT with the utmost respect of course. Well you respect your mom right, so best to respect Mother Nature equally as she can ruin your garden if no homage is shown.
What can I do? Is usually the next thing people ask me?
Well there are many products out there that can help the problem or even eradicate them completely but I do not like spraying my ladies with pesticides or neither do I like treating my soil with any solution or powders as these will eventually be taken up by your plants and I’d rather have my fruits tasting as they should taste.

Myself, I prefer a combination of three methods I’ve tried and tested, which I have to say really do work well in unison.

Firstly, we have to eradicate the root chomping larvae. Acquire a product containing Bacillus Thuringiensis subspecies Israelensis (Bti), “Fungus Gnat off” for example is an excellent choice, what this does is basically send in the cavalry a to deal with the larvae embedded within your root zone. The subspecies in “Gnat off” culminate their attack by producing a toxin that prevents the larvae from feeding on your precious roots, and then they die from starvation.

Secondly, we now have to deal with any escaping larvae. If your pots are full to the brim with your medium and you haven't left enough extra space in your potting pots then you may have to reduce some, around 10 cm deep and replace it with clean SAND, fill to a minimum of 5 cm deep, you can avoid all the kerfuffle by doing this when you initially pot up, saving you headache later.
That's the larvae Gnats sorted and now for the adult ones “muah hah hah haaa”.

Thirdly, ridding your grow area of adult flying gnats. Find yourself a very strong and potent apple cider vinegar, empty the vinegar into bowls and place around the pots. This attracts the adult’s gnats more so than your plants, as the smell to them is too good to pass up; in fact they end up drowning. Well who invited the little buggers anyway? If that just sounds too harsh or you can’t abide by the smell of the vinegar or think you’re a tree hugger and don’t want to drown them happily, you could alternatively put out some insect catchers similar to fly paper. Personally I don’t think that this is in anyway less inhumane as I can just picture the little gits stuck on the fly paper trying to gnaw off their limbs instead lol. It’s your call...