Spider Mites

A marijuana growers worst enemy in the grow room is spider mite infestation. They will reproduce and spread their offspring at a rate that you will NOT be able to keep up with. The spider mite is by far the most common pest found in indoor marijuana grow rooms and they cause the most problems for marijuana growers.

What are Spider Mites?

Spider mites are classified as spiders rather than insects due to the fact that they have eight legs, whereas insects only have six legs. Spider mites are very hard to see with the naked eye, so you will need to use a magnifying glass to see them. Spider mites will first appear as tiny specks on the underside of the leaf. The first sign of your plants being infected with mites will be yellowish-white spots , stippling-on the tops of the leaves. By using a magnifying glass (10-30x) you will be able to identify the yellow-white, two-spotted brown or red mites and their translucent eggs. The most common spider mite indoors is the two-spotted spider mite.

How Spider Mites Damage Marijuana Plants

Spider Mites attack the leaf of the marijuana plant, sucking life-giving sap from plants, causing overall vigor loss and growth stunting. The first thing you notice is the yellow foliage and if its been long enough you will notice webbing around the leaves. The leaves are pocked with suck-hole marks and yellow from failure to produce chlorophyll. The plants lose anywhere from 1%-100% function, which causes the leaves to turn yellow and wilt. Once adult mites have produced eggs and the mite populations have spread, you will most likely need to throw away all plants in the garden or take a high risk of losing your entire harvest. Even if you savage some of the plants for harvest, you will end up with bug filled buds that are not healthy to smoke.

Controlling Spider Mite Infested Gardens

Controlling spider mites in your marijuana garden can be as easy as keeping the room completely clean and sanitized. This process can also be as difficult and costly as removing every plant from the garden and cleaning the entire room, then starting from scratch again. Keeping your grow room clean and free of tools that have been used outside will make a huge difference as most mites travel into your grow room from the outside, using garden tools, hoses, building materials etc. When you first see a mite on your mother plants, you should immediately spray them regularly with a miticide spray designed specifically for marijuana plants, like Azamax by General Hydroponics or Neem oil. This should be done once every three days until the mites have been removed. Keep in mind that once mites are present in your garden they rarely ever disappear for good. They are always present somewhere in the grow room. You should also use the miticide to flush your plants with every 7 days. To do this you simply need to drain the reservoir (hydroponics) and fill with clean water with a pH of 6.4, then add the recommended amount of miticide to the water and then flood your plants for 3 hours straight. Once this is done, you need to flush and refill the reservoir with your water nutrient solution and resume your regular feeding schedule. If you have mites on your plants that have already started budding, you need to be very careful when using any sprays as they can not only damage the resin glands on the buds but can also be harmful when the bud is smoked. I prefer to cut my losses and trash any plant that has spider mite and start from scratch.

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  1. Washing with soap: Boric acid, an ingredient in soap. Also called Roach Proof.
    1/6th tsp in 1 gal. H2o will wipe out millions of trips over night.
    it can be sprayed directly onto veg. The powder left will continue to burn eggs and mites.
    Boric acid is a soil. Spread it all around and nothing will come around.
    A fine layer of this dust will protect for years, or until it is washed off.

  2. killing spider mites on medical marijuana is easy. A new organic cold pressed Neem oil product called Quantum Apocalypse will take care of the problem. I have recommended this product to everyone I know and not one of them has spider mites anymore. The product also works on thrips, whitefly, mealybug, and powdery mildew. I found it at entomo419.com. You are welcome in advanced

  3. ok so i dont want to have the spider mite problem again so the whole room was sanitized, stripped of carpet, revamped another words, now that i am starting from clones before i bring them into my grow room i have dipped them in neem, how often should i do this and or spray as they will get too big for dipping, also should i be sprayibg a few days later with just plain water? and this is just for preventative.

    • i personally would continue dipping once a week until they r too big to dip.. then i would spray them every 3 days until they go into the bud room. dont bring anything in from outside (tools, hoses, pets, etc) each time u go into your grow room, wear clean clothes and just be cautious.. once spider mites are in your room, theres an 80% chance they will always be there… keep clean and keep spraying w neem or azamax. azamax is nice because it can be used w plain water in the reservoir and feds to the plants roots..

  4. Iv’e gotten rid of all plants (closed shop) for 3 months because of spidermites is it ok to start up again now

    • Thats a tough question… ive seen rooms become clear of mites within 30 days, and ive also seen rooms still have mites after 1 year.. all you can do is clean the hell out of it. bleach it using a sprayer pump. bomb it. clean all equipment and keep your fingers crossed.

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