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CONTROLLING SPIDER MITE INFESTATIONS:

Q:   I have tried Neem oil, Organicide and ladybugs [to control spider mites].  I started with the ladybugs -  they didn't work, then Neem - which killed some plants, then Organicide and it keeps the population down but doesn't get rid of them.  What would you recommend next?  Also I am using a clone machine with a heater and Humboldt Roots and a rooting gel under a compact fluorescent light. 

A:  Spider mite control is a popular (although un-popular) subject around here.  The long list of products we've got to offer can be intimidating, but I believe that most all of our product offerings are great alternatives to the chemical sprays you'd find in the mainstream.  I personally think that just about any of these can be effective when used correctly, and the approach you take to the treatment may be more important than the actual spray that you're using.

Wait no longer than 3-5 days between applications: 

Waiting no longer than 3-5 days between applications is, in my opinion, the main key to gaining control.  Just keep going with the sprays every 3-5 days until after you know you've won the battle.  If you wait any longer between treatments, that helps the mites to develop a resistance to your sprays. 

Spider mites avoid the light:

Spider mites avoid the light, so they hang out on the bottoms of the leaves and stems, which is where you should concentrate your efforts with the spray.  

For the same reason, turn your lights off at least an hour before applying any spray, because the dark will bring the mites out from under the leaves, to where the spray can hit them easier.

Use a variety of insecticides:

You're doing the right thing by varying the type of spray.  It's probably best to change to a different type of spray after 3-4 applications of any one kind.  Don't completely give up on the sprays that you've already used, but keep them in your arsenal for future use. 

Pyrethrin based spray (chrysanthemum flower extract) is probably the most common main ingredient for insecticides, and it can work well, but spider mites can develop a resistance to it so you have to use it with some reserve.

Pyrethrin sprays affect your flavor quality the least out of all the different sprays, so it's probably good to reserve the use of pyrethrins (Don't bug me, Dr. Doom...) until later on when you've got developing fruit or veggies on the plant.

Use the heavy oils like Neem and Organocide before your fruiting or flowering has begun, as they can affect flavor quality of developing fruit.   

If you've tried everything else, a series of bombs has proved to be a very effective approach when all others have failed.  We've got two programs of bombs available. 

The first is the Dr. Doom One-Two Punch which uses pyrethrin as it's base in a combined approach of bombs and a manual spray. 

The other is the Whitmere line of bug bombs.  These are considerably more expensive than the Dr. Doom bombs, but have about 10X more concentrated pyrethrins than the Dr. Doom bombs do. Their program is to start with a combination of two bombs - Preclude TR, and Attain TR used together, then begin the 3-5 day approach alternating between Attain TR, and Pyrethrum TR.  The Attain TR bomb is specifically designed to deal with the possible spider mite resistance to Pyrethrins.  Basically, they "tweaked" the pyrethrum molecule in Attain TR so that spider mites that had developed some resistance, won't have any resistance to this bomb.  It's the secret weapon of bombs. 

Predatory Insects:

My last suggestion can be an expensive one.  Ladybugs are OK for preventative maintenance, but not really aggressive enough to get rid of a bad problem.  If you start using ladybugs as preventative maintenance, you've got to continue to release them every week or so, and if you keep it up they can maintain control. 

The expensive approach I mentioned is another live predator called "Triple Threat" spider mite predators.  You can think of these as your insurance policy against infestations if you continue to add them indefinitely your area.  All they do is eat spider mites and eggs, and they don't like the light either, so they hang out in the same places as the mites do.  I'd recommend using these guys in close to the same way I recommended using the sprays, with regular scheduled releases.  If you're treating a bad infestation, start out with a release of the correct number of predator mites once a week for 3-4 weeks (check www.naturescontrol.com for this info), then you can back off to twice a month.  The continued use of them will almost guarantee a spidermite-free environment as long as you follow all of the recommendations. 

Your atmospheric conditions are really the key to successful use with any predators, as you've got to give them the correct temperature and humidity.  The predators are obviously not for everyone.  If you'd like to explore their use, check out our suppliers website at www.naturescontrol.com, or you can buy them from us in the retail store.