Spider mites resistant tomatoes?

[ilex]

I do have lots of mites, just look at my avatar.

[peebee]

And all this time I thought those tomatoes were encased in sheer nylon stockings or bag of some kind . Really? OMG.

[Gardeneer]

Read the following link ( Ohio State U ?) it has good info on spider mites

http://ohioline.osu.edu/factsheet/HYG-2012-11

I have noticed that some of my plants show symptom of SM. That is the leaves looking variegated . I checked and found SM. I have been spraying with Neem Oil. Seems to be working.

[ilex]

Originally Posted by peebee

And all this time I thought those tomatoes were encased in sheer nylon stockings or bag of some kind . Really? OMG.

Those are stored tomatoes and it's common they become like that after a few months. They loose the color, but no farder damage is done. Some consider they protect the tomatoes.

When they are on plants it's a different story...

[b54red]

I don't believe from my experience that any organic method will really stop spider mites when the weather is hot and dry enough for long enough. Another bad thing is most pesticides that you might feel comfortable using on tomatoes will not control them either. I did have some luck mixing Permethrin, soapy water and a growth regulator to be fairly effective but the growth regulator is expensive.

Finally found something that works and it is a combination of Permethrin, Dawn, and DE. It is absolutely the best thing I have found after years of fighting them. For a gallon of water you use about 2/3 cup of food grade DE mixed thoroughly and strained into your sprayer, then add 2 TBS of Dawn per gallon and a dose of Permethrin. The Permethrin and soaply water help kill the adults as well as the soap helping penetrate the webbing and the film of DE left on the plants seems to work well on the juveniles when they hatch out. If it rains hard you have to reapply it and if the weather stays hot and dry then you will have to reapply it eventually to protect the new growth.

I had the worst spider mite infestation this year that I have experienced in 40 years of growing tomatoes. I was able to stop it with this mix but it took three applications over a two month period to totally clear them out. That sure beats spraying with soapy water every two or three days or neem oil every week, or any other mild pesticide every week. I refuse to use a systemic poison which is what they recommend for them down here. The other nice thing about this mix is it is very effective on stink bugs, leaf footed bugs, aphids and whiteflies.

Bill

[Cole_Robbie]

I would be interested to know if the Met52 I use on my whiteflies will also kill spider mites. I don't have any to test it on. I think it would work. Met52 is not officially organic, but it is a harmless-to-people bio insecticide.

[Salsacharley]

Met52 is supposed to be good against spider mites, but it is expensive. My favorite hydroponics store won't sell it because they say misuse can result in a lot of unintended consequences to your plants and possibly to yourself. I don't know the specifics about it.

I've been using Monterey 70% Neem Oil and I mix it with Monterey BT so I can deal with spider mites, aphids and horn worms in one spraying. Since I've got 120 plants to spray, any efficiencies I can get help a lot. I used to use DE mixed in but it was clogging my sprayer. I now have a 12 volt power sprayer with a 9 gallon tank and that has really boosted my willingness to spray regularly.

http://agrimart.net/master-mfg-garde...page=2#reviews

I've used this sprayer about 10 times and it works awesome!

[ilex]

"Colgar cerruo", that is the variety that looks quite good among the almost dead neighbours. Very visible difference. We should test it again next season and see if it was just growing over "something" or there are some interesting genetics here.

Looking for a couple volunteers that want to test its spider mite tolerance.

[zipcode]

I am pretty sure not all tomatoes are as infested with pretty big variations even.
I think it's a matter of 'optimal food'. The predator mites don't really multiply well unless they eat the preferred mite. I think that's the case here as well. They will eat them but not multiply as much on some plants.
Otherwise I can't explain the difference in some varieties being infested while touching the leaves of others barely with a few mites (and same varieties each year).
So Pink Berkley Tie Die has been the least attacked two years in a row, with Galina being most terribly eaten. I have two spotted mites.

[Cole_Robbie]

Originally Posted by Salsacharley

Met52 is supposed to be good against spider mites, but it is expensive. My favorite hydroponics store won't sell it because they say misuse can result in a lot of unintended consequences to your plants and possibly to yourself. I don't know the specifics about it.

I get the feeling hydro store guy might be on something that makes him overly paranoid, if he thinks Met52 is hazardous to people. It's a mold spore, and they tell you that people who are sensitive to mold allergies should use a respirator mask when spraying. But I'm not. I keep my Met52 in my refrigerator...next to my food. I am very confident about it not being hazardous.

[Dewayne mater]

Given the way they multiply, resistance is futile under hot dry conditions. Meaning, you have to treat them, not rely on a plant to be able to withstand them. I sprayed a few times with DE, soap and permethrin, but, went on a vacation and got back to a typical awful infestation of the red devils.

This year, I treated my early spring garden with nematodes in March that seemed to keep the pests in manageable numbers until it got hot. Stupidly, I did not keep that approach up in the summer when a different type of nematode is available that can withstand the heat. I would be curious is anyone has had luck with some of the heat thriving nematodes that feed on spider mites and other plants?

[b54red]

Originally Posted by Dewayne mater

Given the way they multiply, resistance is futile under hot dry conditions. Meaning, you have to treat them, not rely on a plant to be able to withstand them. I sprayed a few times with DE, soap and permethrin, but, went on a vacation and got back to a typical awful infestation of the red devils.

This year, I treated my early spring garden with nematodes in March that seemed to keep the pests in manageable numbers until it got hot. Stupidly, I did not keep that approach up in the summer when a different type of nematode is available that can withstand the heat. I would be curious is anyone has had luck with some of the heat thriving nematodes that feed on spider mites and other plants?

I get it about leaving and them taking over again. During the peak heat if you get a good rain and it washes off enough of the DE they will return quickly and even without a rain new ones show up on the new growth so a couple of sprayings is necessary to really keep them under control. I ended up having to spray 3 times and if they return during this present heat wave I will spray again. The DE, Permethrin, and Dawn mix really works but it isn't everlasting and so needs to be repeated if the infestation is heavy or the weather is overly conducive to mites. I have added copper to my mix so that I now take care of most of my fungicide needs at the same time and have seen no reduction in mite control with the new mix. I use one TBS of Southern Ag copper fungicide to the gallon of mix.

Using the new mix I have seen a real reduction in gray mold this time of the year when I have a lot of black tomato varieties growing. It has also helped with speck and spot problems which can get bad this time of the year. The other bonus of this mix is I am seeing no stinkbugs, leaf footed bugs, aphids, or whiteflies so it is a disease reducer just by limiting these carriers. I also have seen no hornworms since the first treatment for spider mites so maybe it is getting the juveniles before they can grow up.

As to the DE clogging your sprayer it is important to strain the DE after mixing it with some water before adding to your sprayer and it is also important to keep agitating your tank occasionally along with keeping good pressure pumped up so it flows quickly through the spray wand and nozzle. I haven't had a clog this year and I have sprayed 9 gallons of mix through the sprayer so far this season and I didn't see any last year after the first time I made the mistake of mixing the food grade DE directly in the sprayer. It is also important to use the food grade only since it is so much finer than any other grade of DE and suspends well in water and stays suspended if it is agitated regularly.

Bill