TetraSan on flat mites -- thoughts, anyone?

[Steve Johnson]

Those bloody effing flat mites continue to be the bain of my existence. In fact they've turned out to be more of a problem than I thought, since they're having fun playing hide and seek with the weather -- when the days warm up they like to nibble randomly on a number of my plants, and when the days cool down the mites take a nap. My daytimes since the beginning of March have been all over the place, so trying to chase after these pests with IPA has been, shall we say -- ...

Dean Stock has spoken highly of TetraSan a few times before, although his latest post in my Flat mites on the attack thread left me quite intrigued about pursuing this seriously. Here's what he said:

Orchid growers found the solution to mite problems decades ago and there are products that are easy, safe and effective to use on cactus as well. Try Tetrasan at 1/4 tsp/ gal as a spray and you should get rid of them. A second spray may be required during the season, but since Tetrasan is a powerful ovacide you generally will not get resistance or have a second population develop after the initial spraying due to hatching eggs. I'm not sure that Tetrasan is labeled for cacti but I've used it on several genera and have not seen any problems. Tetrasan is also one of the least toxic products for humans (mammals in general) for use in the greenhouse. I know the product is available in the U.S. but I don't know about E.U. I got mine from Hummert International.
Dean

I checked into it, and TetraSan is certified by the state of California, so I can indeed get it for home use. Now I'm excited, and Bayer 3-in-1 spray may not be the only alternative I have to endless applications of IPA. However, before I pull the trigger, let's review the facts, then I'll pose a couple of important follow-up questions.

First, here's the data sheet on TetraSan from Valent BioSciences -- please review this if you're not familiar with the product and how it works:

http://www.valent.com/professional/prod ... geid=74005" onclick="window.open(this.href);return false;

According to Valent, TetraSan is effective against Citrus Red Mite, European Red Mite, Lewis Spider Mite, Pacific Spider Mite, Southern Red Mite, Spruce Spider Mite, and Two-spotted Spider Mite. Unfortunately, flat mites (AKA false spider mites) aren't on the list. I emailed Valent to ask them if the product is known to be effective against my nemesis. They haven't responded yet, and while I was waiting, I posed the same question to a couple of outfits on eBay that can sell TetraSan in the small quantities I need. The Landscaper Store claims that the product should work, but happygarden 685 hasn't responded yet. The one response I've gotten may be okay, but I'm not satisfied enough to be confident that the people at TLS know what they're talking about. So there's question #1 -- does anyone on the forum know for a fact that TetraSan will indeed be effective against flat mites?

Paraphrasing what Ian said elsewhere on one of my flat mite threads, this pest is perhaps the least known among cactus growers. The possibility that it's fairly recent arrival to cacti under cultivation certainly doesn't help if there aren't enough people with direct experience telling us that TetraSan is effective against them. While I don't have much use for the general gardening forums, I may expand my search for answers in case flat mites attack plants besides cacti. If I get valid answers, it'll be the one time when those forums actually turn out to be helpful. However, I'm prepared for the fact that in the absence of solid responses, I may have to be the point man for a TetraSan experiment. As the weather heats up again heading into the rest of spring and summer, I'll certainly have the opportunity for catching flat mites in the act when it happens. This leads to my last 2 questions -- and my friends, they're really important:

1. Are there any cacti that could have a phototoxic reaction to TetraSan? Whenever I spray my plants (whether it's IPA or just plain water), I always do it after sundown, so they're dry well before the sun comes up again. If I follow the same practice with TetraSan spray, I'm hoping that it takes the risk of a phototoxic reaction off the table. With that said, I'd rather be safe than sorry, and I'll really appreciate any feedback on this yeah or nay.

2. If I'm getting a thumbs-up from TetraSan so far, I'll follow Dean's advice on diluting it at 1/4 tsp. per gallon of water for spraying. @Dean -- is TetraSan powder only, or does it come in both liquid and powder forms? I just need to make sure that I'll be using the product at the correct dosage.

I'm a persistent pup, so I'll keep going with this for what I hope will be a good outcome. I'd just love to ditch the IPA before I have to go through another growing season of constant flat mite inspections!

Thanks for any thoughts y'all would care to offer here!

[A. Dean Stock]

Steve, I can't answer all of your questions regarding Tetrasan but regarding phytotoxic effects, I have used it on all of my orchids and cacti. Only grow SW U.S.l forms of cacti so I can't say much about others but see little reason to be concerned. It is a good bet that the product would not be anywhere near as bad for any cactus as a mite attack!!!
The product is labeled mainly for agricultural use and hence lists only those species of mites most commonly encountered by produce growers and major crop plants. It costs too much in time and money to list every species that the product might be useful on. Since a plant feeding mite is a plant feeding mite no matter what the color or shape, I think that it is highly likely that the product would be effective against "flat mites" on cactus. I would cost you little and probably save you lots to give it a try. I wouldn't be without in my greenhouse. Hope that helps.
Dean

[Steve Johnson]

Steve, I can't answer all of your questions regarding Tetrasan but regarding phytotoxic effects, I have used it on all of my orchids and cacti. Only grow SW U.S.l forms of cacti so I can't say much about others but see little reason to be concerned. It is a good bet that the product would not be anywhere near as bad for any cactus as a mite attack!!!
The product is labeled mainly for agricultural use and hence lists only those species of mites most commonly encountered by produce growers and major crop plants. It costs too much in time and money to list every species that the product might be useful on. Since a plant feeding mite is a plant feeding mite no matter what the color or shape, I think that it is highly likely that the product would be effective against "flat mites" on cactus. I would cost you little and probably save you lots to give it a try. I wouldn't be without in my greenhouse. Hope that helps.
Dean

Well, time to get me some TetraSan then. Thank you so much!

[BarryRice]

Steve, have you looked at the price for Tetrasan? Pretty spendy stuff, you be spending about $100...

[Steve Johnson]

Pretty spendy stuff, you be spending about $100...

Actually, no -- I just purchased a 2 oz. packet of TetraSan for $30 from The Landscaper Store. I know that still sounds expensive, but A. I can afford it, and B. the dosage recommended by Dean is 1/4 tsp. per gallon of water for spraying. At that rate, my 2 oz. of TetraSan will go a long, long, long way given how small my collection is. Since we still have plenty of growing season left, this is an excellent opportunity for putting TetraSan to the test. While I can't expect that one or two applications are going to be enough to keep the flat mites away for good, more effective mite control would definitely be worth the price of admission. If my cacti are relatively mite-free this year, I'll sure as heck let y'all know about the good results.

By the way, Barry -- I'm afraid you were right about Dyna Gro. Wasn't paying enough attention to what you said in one of your PMs until my brain finally woke up when I whipped up a gallon of my watering solution last night. As you said, like the sound of gravel rattling around in the bottom of the jug. I don't want to go too far OT here, so I'll be talking to the Dyna Gro people to find out what the heck is going on. I'll send you a PM with my findings as soon as I can, hopefully later this week.

Thanks for your feedback, guys. And special thanks to Dean for his recommendation on TetraSan!

[BarryRice]

Steve, I've talked to Dyna Gro folks and have the fix for you. I'll post a note about this later.

[Steve Johnson]

Steve, I've talked to Dyna Gro folks and have the fix for you. I'll post a note about this later.

I had a really nice and detailed conversation with Raphael at Dyna Gro this morning. Send me a PM, and let's compare notes. Good to know that I won't have to consider throwing my jug of 7-7-7 away after all!