Drying soil slowly vs oven to reduce pests?

Discussion in 'Growing Organic Marijuana' started by gnatfree, Jun 24, 2015.

  1. Total noob time-warping back to my 70's youth....


    Very small grow, I have one bag of "PRO-MIX Ultimate Organic" 1 CU/FT


    I'm trying to play it safe and wonder is there any benefit to air drying the soil (indoors) to break the gnat cycle?
    There may be none in the bag, but to be safe I'd like to try something?


    Will air drying be better for the soil than baking it in the oven?
    Or...should I just not even bother drying/baking and just use neem to control anything that might crawl out of the soil?


    My other idea was to just set out a pot, water it and wait to see if gnats emerge after a week or so - that way I can know for sure before I put my plants into the pots in my grow room.


    Thanks for any tips!



     
  2. #2 pointswest, Jun 24, 2015
    Last edited by a moderator: Jun 24, 2015
    If you are planning an organic grow you don't want your soil sterilized, you would be killing all beneficial organisms in the soil. If you get fungus gnats it is most likely from poor watering practices, not brought in with the soils. Many growers blame the soil products, when in reality it is their own inexperience and poor cultural practices causing the problems. Fungus gnats are one of the easiest pests affecting cannabis grows to control and should not be a problem, a couple of drenches with Gnatrol will control most outbreaks if watering techniques are changed to avoid constantly wet soils on the surface. When a grower learns proper watering techniques, you should not experience an infestation of gnats in the grow.


    PW

     
  3. Avoid killing the life in your soil sphere! and add some neem cake, that neem is addictive ..as I use the oils for preventing molds and all bugs
     
  4. Neem cake meal = no more flying insects (period) as mentioned... and seconded ... top dress is good enough for gnats. 1/2 cut sprinkled on the surface... that's the cure. There are others, this is the best.


    Just to be clear - gnats are a sign of living soil, which is NOT a bad thing. At most fungus gnats are an irritation, if not brought in the compost you're using, then you're soil is too wet. Stick finger in soil up to first knuckle if damp wait till tomorrow to water. Better to underwater than to over water. When you under water your plants will tell you right away they are thirsty. Over water and plants will DIE a slow death, the start of which is fungus gnats.

     
  5. so true! i noticed it can take a plant weeks (if at all) to recover from over watering but merely a few minutes to an hour to recover from under watering.
     
  6. #6 ladyluckybean, Jun 30, 2015
    Last edited: Jun 30, 2015
    Aren't you supposed to keep the top soil moist and that's one of the points of adding mulch? I added a thick layer of neem and that still didn't work. I read they feed off of organic matter and decomposing materials so it seems to me that they are attracted to that. How come you recommend keeping the topsoil dry? Thanks :)
     
  7. #7 Sc00byD00bie, Jun 30, 2015
    Last edited by a moderator: Jun 30, 2015


    i think gnats prefer a moist top soil to lay their eggs in, keeping it dry will make it less appealing to them.
    i think the idea with mulch is that the mulch stays dry while keeping whatever is under it moist.


    i found the best way to deal with gnats is to not worry about them. keeping with a regular IPM has reduced them to single fliers i spot sometimes. i keep a couple of yellow sticky traps out and i dont worry about it unless i see a bloom.
    i think the fact that my soil is full of different critters is really whats helping to keep them at bay, i bet the centipedes enjoy munching on their larvae!

     
  8. sorry I don't think I communicated that right. I know that dry topsoil will help like you say but I thought that was supposed to stay moist for your microbes and such. so if I took the mulch off and dried out my soil, how is that benefiting beside no gnats? seems like it would hinder it. would my worms be okay with this? I always have them and last time they stuck to all my buds. how gross is that?! [​IMG]
     
  9. Top dress with diatomaceous earth ?


    Sent from my iPhone using Grasscity Forum
     
  10. You're correct in your context LLB, keeping organic soil somewhat moist is always preferable to overly dry conditions since many microbes will go dormant in the absence of adequate moisture levels and worms will evacuate pots. Be that as it may we want to avoid constant over moisture conditions from the soil surface and top dressing will aid in doing so. It's a balance really is what we are trying to achieve, a balance of moisture without over moisture levels.


    Fungus gnats are always around in my garden but they rarely get out of hand and when they do I use BT brics and some glue traps to bring down the population, that and I sometimes spray the walls/floors of my room with some Pyrethroid spray to pick up the stragglers.

     
  11. Do you think a SIP would solve this issue?
     
  12. i still see them sometimes around my 1gallon mother sips, maybe in bigger smarties it would be more effective against them.
    do you have a thick mulch layer?

     
  13. #13 ladyluckybean, Jul 1, 2015
    Last edited: Jul 1, 2015
    I removed it to soil drench and eliminate hiding spots for the mites. I used around two inches of ewc and kelp/crusty/neem added. Under that was a 1/4 inch thick layer neem and below that whole comfrey leaves. I'm going to add straw when I get my 20 gallons in the mail. I've added lots of Bits and used a liquid bti as well as nemotodes. Still going through a plague. Yellow traps are full within a few days :(
     
  14. they are annoying that's for sure! have you tried the neem/kelp tea? i just did one today.


    here's another idea [​IMG]
    5669-004-B4BF1047.jpg


    hope you get them under control soon!

     
  15. found this recipe from cc in my notes, maybe worth trying as well: (cant seem to get the quote function to work)


    So while you're at Whole Foods pick-up Cilantro (organic ONLY) and when you get home toss the entire bunch (sans the tie around the middle) into a food processor with enough water to make a slurry or puree.

    Add this to 1 gallon of clear water and let it sit for 36 - 48 hours. No more than this.

    Add 1 cup of strained Cilantro tea to 15 cups of water = 1 gallon. Allow for 1/4 cup of Aloe vera juice and use 1 tsp. of Pro-TeKt.

    Wait until the it's almost "light's out" and spray the top of the soil, every branch, every leaf from top to bottom. You want the plant to look like you haven't watered in several days and it's drooping big time.

    Leave the ventilation system going and by morning you won't have anything hopping, flying, whatever in your chamber. Follow this up every 4 days until you're completed 4 applications.

    Done. Finis. Ovah.

    This is not a pesticide in the usual definition and without a long explanation you might need to trust me on this one - I apply this and other 'Mint' teas to hydrate the soil every couple of weeks.

    "Bio Stimulants"


     
  16. #16 ladyluckybean, Jul 1, 2015
    Last edited: Jul 1, 2015
    I tried that recipe actually and it didn't do zilch with the mites and spraying it around the room didn't do anything that I recall. I've used neem kelp teas several times making them very strong too. I check the next day and still there. no dent.
    spinosad, essential oil, neem oil, neem tea, fix it mix, crab meal, crustacean meal, kelp meal, neem meal, soap/water drenches
    nope
    so I'm thinking they're coming in there from somewhere else. maybe my worm bin which is right next to it or the humidifier that has an open way to com in there. a frog has taken up residence in my worm bin to feast on flyers. he sits on top of the 6 inch layer of mulch I put on top to keep it moist.
    I saw your cape sundew or what ever it's called and I have actually thought about using that but there is some technical things about raising those indoors. the sundew one is the best for indoor grow lights. I almost bought one but figured that these are well known to be tempermental delicate plants and I have enough of those right now.lol
    thanks for looking stuff up Scooby! appreciate it!
     
  17. Have you treated the worm bin with BT? I have used it in there without issue and worm bins are well known for housing massive populations of fungus gnats.
     
  18. #18 ladyluckybean, Jul 1, 2015
    Last edited: Jul 1, 2015
    I've added it to the fabric beds and the water in my DIY humidifier as it's open but not the worm bin. I heard people have better results using crushed up dunks over the bits. I was going to try that in the humidifier and a different liquid bti in the soil. can adda few dunks in the bin I suppose while I'm at it. :)
    Haggard stopped by and gave me some advice on my thread and it's all the advice I've heard but he put it into steps sorta. I only add 3-4 gallons every 5-7 days in a 100 gallon bed. is that over watering??
    DIY humidifier link http://forum.grasscity.com/do-yourself/1369455-diy-humidifier-small-large-grow-rooms.html?hl=humidifier#entry21775659


     
  19. That's what I use, the crushed up dunks in my worm bin. As for Haggard's advise, I don't know what ratios you should use for that but 3-4 gallons per 100 gal soil shouldn't be over moist no, just use the add a little and check method.
     
  20. mulch well and keep a good breeze at the soil line, and you won't have gnats. They are horrible fliers, and if they can't land in the soil then they won't stick around.


    haven't seen one in my room in a really long time.

     

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