cannabis pestsHow to get rid of spidermites:

Anyone who’s ever suffered from these pesky pests will know what a blight they can be. I’ve even moved house after unsuccessful attempts to be rid of them! Having now found how to get rid of spidermites completely I’m delighted to be able to share the news with you.

But first, a bit of background for those who aren’t quite sure if spidermites are their problem:


What are spidermites?


There are about 1200 species of Tetranchidae, but the one that most effects the cannabis grow room is the one commonly known as red spider mite. Not actually red (its only the adult females that develop a red tint with age) they are usually a translucent light greeny/brown shade, less than 1mm in size with 6 legs and two dark spots on either side. Spidermites lay spherical transparent eggs on the undersides of leaves which hatch in just 3 days and become sexually active 5 days later. The eggs are often protected by a fine webbing although this is often not apparent until numbers start to increase. But don’t relax about this fact as an adult female lays 20 eggs per day, and within 8 days each of these is capable of contributing another 20 eggs a day to the infestation ..

spidermites cannabis

What environment encourages a spidermite infestation?

Guess what! Your grow room environmentals are just perfect for spidermites. Unlike many pests or diseases where its an imbalance that’s to blame, with regards to these cannabis pests its the ideal grow rooms which are most vulnerable. Spidermites like it hot and dry which is just how your tent is during flowering.

However there are some bad habits which encourage spidermites:

  • a dirty grow room: spilt compost and leaf litter give the pests somewhere to hide and make dealing with the problem more difficult
  • poor airflow

What damage can spidermites do to a cannabis crop?

Its as bad as it gets – a heavy spidermite invasion can kill your plants. And the issue isn’t always with the current crop – because they have a “zombie like resistance” (thanks Nebula Haze for that accurate description) to pesticides, which combined with their incredible reproduction rates means they are likely to keep on coming back and back in greater numbers, it can signify potential doom for future crops too. You can see why I once moved house to be rid of them.


 The first signs of spidermite:

If you can see clusters of yellow/white pin pricks on the tops of the leaves, look underneath and see if you can spot any adults. Use a LED microscope to help you do this (it comes in useful at harvest time anyway). As numbers get larger, you’ll be able to see the fine webs especially if you spray the plants with water.


 How to get rid of spidermites from your grow room – for good!

I’ve battled with spider mites on a couple of occasions and am always on the lookout for this pesky pest. Ways you can try to combat it are:

– Azamax
– Mighty Wash
– Alcohol and water
– SM-90
– Neem Oil
– Homemade Pepper Spray – 9 parts water, 1 part dish soap, plus 1 tablespoon of cayenne pepper
– Nicotine tea
– NoPest Strips

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how to get rid of spidermitesBut the way I got rid of spidermites completely was due to one product: B.A.C.’s Plant Vitality Plus.  The horror story picture I put above is actually from my grow room, where I allowed one small tent to get into this state. I sprayed with the Plant Vitality Plus, then the next day cut back the plant removing all dying and dead leaves. They came back healthy, pest free, and my grow room remains clean and clear of bugs 4 months on. [/su_box] [maxbutton id=”5″]




Of course, prevention is better than a cure. Here are my

5 easy ways to stop spidermites from taking hold in the cannabis grow room:

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  • Keep your room tidy: its just good practice to remove any decaying plant matter and rubbish from the area
  • Make sure you have good airflow running through the room and a strong enough extractor to pull stale air out
  • Don’t pull your intake air directly from the outside, and if you have to, use a mesh type filter to stop bugs getting in (Homebox’s new Evolution Grow Tents actually come with a patent pending OMNI AIR vents which have this built in!)
  • Try and prevent the bugs coming in on clothing, other people and pets.
  • Quarantine cuttings in a separate area before introducing them to your actual room. [/su_list]


3 thoughts on “How to get rid of spidermites from your grow room

  1. Duke Deltree says:

    I use sugar water spray sticks their little faces to the leaf, legs. they hate it you will rinse with fresh water after a while and repeat till they are gone remember the eggs all it takes is a few so in two days re apply sugar water I think brown sugar is to much so use white refined

  2. David says:

    Best non-toxic spider mite treatment is Method 1-pps from Growth Efficiency Technologies. Works well and leaves the plants clean and free of toxic residue.

    • weed widow says:

      Excellent information! Thanks for sharing .. I think with something as bad as a spidermite invasion all tried and tested products are good to know.

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