Hello. I've been looking round this site for a few months now and can't find any answers to this question. Also looked around Google and still no answers. So sorry if it has been answered previously I am growing 8 various autos in a 4x4 tent with 900w of hps/mh lights. I'm growing in soil and compost and have had a slight problem with fungus gnats which I managed to get rid of but one or two are still in tent and I don't want to encounter this problem again. also the surface of my soil dries out pretty quick. Other than this the plants appear to be growing pretty good. My question is can I cover the top of my plant pots/soil with a cover like a paper plate or cardboard sheet or weed block material and mulch to stop the soil drying to quick and also stop the gnats. Will this work or will it cause any further problems such as mould or root problems. Thanks for any help and input.
You want your soil to dry out. This gives oxygen to your roots, also will help with your gnat problem. Sent from my iPhone using Grasscity Forum
You con top ur soil with sharp sand fungus gnats dont like it an wont lay eggs on it an shld help retain some moisture but as the post above me says u want soil to dry out as roots need oxygen 😆
Could u top with perlite? U likely already have that. But as mentioned above you could buy diatomaceous earth and rest easy knowing them fuckers are getting sliced up like Jason on a rampage guarding your soil. . Haha Either way GL with the grow
Thanks very much for all the answers. I will try the sand and drying soil but I was a little worried about the plants drying out and out but I don't know where to get diatomaceous earth from. I have seen posts and comments about this before and I am in the UK
Sorry about last post. I sent it while half way through writing Thanks very much for all the answers. I will try the sand and drying soil but I was a little worried about the plants drying out and I don't know where to get diatomaceous earth from. I have seen posts and comments about this before and I am in the UK and can't find any local shops or stores who sell it.
In the US, one can typically source DE at auto parts stores. They sell if for absorbing spilled oil, and this will be your cheapest option because it's not marketed for grow enthusiasts. Just make sure that the ingredients label lists nothing other than "diatomaceous earth" or "marine diatoms". Steer clear if you see any other ingredient that looks "chemical" in nature. Have you checked nurseries and garden supply stores, as opposed to grow/hydro shops? Apply liberally to the soil surface and work in gently to about an 1/2"-3/4" depth. It's pretty much non-soluble, and will have a much more noticeable effect compared to using green sand (think tiny shards of glass compared to rounded grains of glass...). This will take care of newly hatched larvae moving up through the soil, as well as burrowing adults that are unfortunate enough to rub up against it. Get some yellow sticky traps to catch air-born adults. Catch 'em above the soil so that they can no longer breed and lay eggs in the first place... MULCH is what you want to slow evaporation in the top soil layer. There are many, many kinds. Straws and hays are the most easily sourced, and are rather cheap. Free even, if you don't need a lot and can find a supplier/source that will allow you to collect "scraps" from the storage floor.