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Need help with bugs? Have spider mites and gnats?

Discussion in 'Bugs' started by Nander, Nov 26, 2012.


    Nander Member

    About a year after I first started growing in the tiny space that I have, I ended up getting both pests pretty regular. They go away, and come back on the wind, or with soil.

    Spider mites as far as I know like it hot and dry. So you should make the grow room cool and humid. Unfortunately this makes it a slightly better environment for fungus gnats.

    For fungus gnats in a closed space, I have been using the carnivorous plant known as the cape sundew. Fungus gnats are drawn to it like a magnet and are devoured almost instantly. All one needs is peat moss and rain water to grow a sundew.

    To kill spider mites I have had a lot of success with oil. I tested rosemary oil and ivory dish soap on spider mites and on two inch long green caterpillars and it killed them both.

    The spray I have come up with though is actually neem oil and rosemary oil together. Smells like pinesol. In one quart of water, add a few drops of ivory soap. Measure out 1ml of both rosemary oil and neem oil and mix well with your one quart of soapy water. Mix very well, and if there are no suds you might want to add a tiny bit more soap.

    You may want to trim your vegging plants down to a smaller size to help with the amount of spraying you will need to do. As far as flowering plants, if they are late in flower, as in, they have some pistils turning brown, you're better off waiting for the next grow. But early on in flower you can spray for mites but try not to soak the flowers themselves.

    At too high concentrations of rosemary and neem oil you can burn your plants leaves. Be careful to not use more than 4ml of oil per quart of water or you could severely extend the time it takes the plants to recover from the infestation and the spraying. Plants do not enjoy wet leaves. To dry off your plants place them back in your [cleaned] grow room with the lights off but ventilation on.
    Vincent VonBlown

    Vincent VonBlown New Member

    I'm about ready to give up on soil, to much work, and now it seems like even my fav soil. That didn't use to come with bugs, is now full of them like the rest of the packaged soil product I've found.

    jcurtis912 Active Member

    I noticed something about soil that you might find interesting. For one soil, IMHO smokes better, smells better, tastes better. But you are absolutely right, if you use soil, you will always have at least a slight bug problem. HOWEVER, i have found if you go all organic, and have a very diverse ecosystem in your pots, the bugs seem to keep each other in check. Meaning, this bug eats this bug, who eats this bug. Keep away from the chemicals, and the problem will balance itself.

    Widespread Member

    I don't think those little gnats harm the plants, do they?

    Spider mites are another matter. I use neem oil concentrate, diluted. I've never used rosemary oil; does the combo work better than neem alone?


    brimck325 Well-Known Member

    gnat larvae suck on the roots and can kill a plant. i dont fuk around with mites, i use azamax. good luck...

    Widespread Member

    Huh, interesting. I get a few gnats, just 'em with my finger. It's easy in a 5 sq. ft. Cab. I could see it being more problematic in a larger space. I got spider mites last grow, noticed them when I started checking trichs. Revolting buggers!

    GreenThumbSucker Well-Known Member

    If there are no dead roots to feed on, the gnat larve will start eating healthy roots. Some cedar chips from the hardware store on top of the soil or hydroton will keep the adults away. You can also use those yellow sticky things that stick in the soil to get adults. Diadmacous earth sprinkled on the soil surface will keep the larve from penetrating the soil, it cuts them up. An inch of sand on the top of your soil will keep the adults from laying eggs.

    The gnats like moisture. Allowing your pots to dry out completely between waterings will help keep them at bay. You can also use cedar oil products like gnatrol in your solution to keep the adults away.

    For mites just go all out nuclear on them and use Forbid 4f. You can get small amounts of it on ebay. 1 ml makes a gallon of strong spray. Just spray on top of the leaves and it kills both eggs and adults and keeps killing for 6 weeks. Only use during vegetative stage. You only need to spray them once per crop with this stuff. Its that strong. Do NOT use during flowering.

    slowbus New Member

    I always thought that for years.Until last week I was proved wrong w/some killa 'dro

    Nander Member

    Something I noticed -a lot- with soil and growing weed in general. Your product and the whole plant itself will both taste, and smell exactly like what you are growing it in. I know because I used miracle grow the first few times I grew. The buds were dense, compact. The plants were beautiful. But they smelled and tasted horrible due to all those chemicals.

    I use a mix of bio fungicide Promix, and fox farm ocean forest. Fox farm smells totally amazing, and promix isn't bad either. I grew one plant in homemade completely organic compost that I use in outdoor gardens, which is mostly earthworm castings. That plant smelled and tasted great when smoked too.

    As far as fungus gnats go, yes, they can definitely do a lot of damage. Get your plants just the least bit stressed and wet, and fungus gnats can attack and make your plant grow even slower. Most plants can outgrow the damage done. However, if you are trying to root clones in soil as I do, fungus gnats are deadly. They pretty much can completely prevent your clones from ever taking root. If they are not controlled some how.

    I tried neem oil alone for spider mites and it did not work at all. It just kinda slows them down.

    The first time I used rosemary oil, purchased at any health food store for like 7$ for a single ounce of oil that can be used to literally make 30 quarts of treatment or more, It killed the spider mites -on the very first treatment-. I got out a magnifying glass and looked for and found the corpses to prove it. Crawling around before spraying, dead and dry after. It kills spider mite eggs, too.

    Rosemary oil does not only work on spider mites, but on aphids or any other bug that is attacking and eating the leaves and stems of your plant. It even will work on large insects, such as caterpillars.

    I just like to mix neem and rosemary oil together. 1ml per quart of neem oil and 0.75ml ~ 0.50ml of rosemary oil per quart. 3 drops of ivory soap or other mild detergent. Its like nuking the tiny bastards. They hate it. :) And they do not seem to devolope a tolerance either. I believe the neem oil helps protect your leaves from getting burned by the rosemary oil.

    Remember, if you buy that SNS at the grow shop they will be charging you like 20$ ~ 30$ for what you can make yourself for a fraction of the cost each time. You will be ready any time the mites strike, too.

    Nander Member

    Oh. The cape sundew. Its a truely beautiful plant. Its got long elongated leaves with sticky balls of goo on the end of long bright red hairs that completely cover each leaf. They smell sweet to all flies and gnats. Its basically like your own personal, ever growing yellow sticky trap. ENJOY THIS VIDEO OF A SUNDEW EATING

    These plants happily grow in smaller pots of pure sphagnum peat moss. They like being kept soggy, which further attracts the fungus gnats. These plants work great as protectors of clones and to grow around the root balls of larger plants. Also, the larger your fungus gnat problem is, the bigger your sundew will get.

    As for watering you must -never- give your sundew -any- kind of food -or- mineral or your sundew -will- die. -Only- give your sundew steam distilled, reverse osmosis filtered water or even better, water from rain or snow.

    One final note on growing the sundew is that any sudden -increase- of light such as trimming back your crop or removing several plants, or moving the light closer can severely burn your sundew.

    Also, if they grow a flower stalk, basically a hairy thing with balls on the end, carefully snip it off. This will cause the growth of more leaves.
    sup@baked likes this.

    zack66 Well-Known Member

    That cape sundew plant sounds good. I'll look into it. Have been struggling with fungus gnats. Last bale of pro mix was loaded with them. Got some clones just starting. Want to kill those little fuckers before it gets out of hand. Have tried strips, Azamax, non diamtceous earth. Nothing is really doing the job. In all fairness to Azamax I didn't put enough in my medium to really be effective. That shit is expensive. Especially trying to treat 9 plants in 5 gl buckets. Thanks for the tip though!

    Nander Member

    Yeah, I am on low budget myself. Can't afford the spray you buy at the grow shop. I bought one cape sundew, and as it grew i put it in larger pots. In the process it had babies because of all the fungus gnats it ate. I transplanted one of them and now I have four plants. It will never eliminate the gnats, as they are always present in soil. However what happens is the plants actually become dependent upon the level of fungus gnats that come out of the soil. Meaning suddenly there are no more gnats for the plants to eat and you have to go hunting for bugs for them to eat to keep them alive and sticky.

    Fortheloveofgreen Active Member

    I read somewhere that if you slice a potato and lay it on top of the soil, the larvae with go to it, which then you can dispose of the potato easily..

    Have no proof it works. Just information, or misinformation as the case may be..

    Nander Member

    Yeah I both heard and read that you can use a potato. Fungus gnat larve are like 3mm long, if that. They are nearly microscopic. But I saw them crawling on the stem of a clone I was trying to root. It died.

    I tried the potato trick, but it just seemed to dry up without doing much. I did not see the crawling maggots.

    Also A question. Does anyone know the difference between a fruit fly and a fungus gnat? They look the same. :/

    smokebomb1 Active Member

    I have been using avid miticide for years and have never ever seen a single mite in all the time i have been using it. You MUST use it properly! Only two doses needed, once in early vege and once before switch to bloom. It is not like other miticides that dont work unless you drench the entire plant many times for effectiveness. When used PROPERLY it penetrates the tissue of the plant and keeps killing up to 25-30 days. Most others only leave a residue that only kills for a week or so resulting in mites that are able to resist the poison. You need a wetting agent with avid, mix 1ml avid and 4ml wetting agent per gallon and spray. Avid is expensive but one bottle should last you a lifetime.

    smokebomb1 Active Member

    Btw, gnatrol for gnat larva is best for control of the little fuckers. Use as recommended and it works wonders.

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