Dare I???

[Hermitian]

Originally Posted by peebee

Raybo, checked the bottle and mine has "RTU"(so, ready to use, not concentrate) after the same title. The ingredients appear to be much weaker: Pyrethrins 0.01%, Canola Oil 1%, rest is inactive ingredients. No wonder it did squat. Thankfully it was a gift, at $10 puny 22 oz bottle. The artwork was EXACTLY the same too, as Hermitian suggested.

Originally Posted by rnewste

peebee,
See the label on the bottle in my post above. Much more potent than what you used.
Raybo

The RTU bottle is designed for hooking up a hose and spraying out directly. The built-in mixing ratio is much higher than the mixing rate listed on the concentrate bottle that Raybo has. If you both followed the labeling instructions, then you both sprayed the same concentration.

[rnewste]

Richard,

I'm not following your math. The RTU hooked up to a hose is going to further dilute the Pyrethrin 0.01% and Canola Oil 1% by at least 100-fold.

The Take Down concentrate shown in my post starts out at Pyrethrin 0.5%, and Canola Oil 89%. This get mixed at the rate of 1 ounce into 1 gallon water in the pump sprayer (a 1 to 132 ratio).

This seems to my calculation to be a much higher potency that the RTU bottle diluted through the hose spraying. What am I missing??

Raybo

[Hermitian]

Originally Posted by rnewste

Richard,
I'm not following your math. The RTU hooked up to a hose is going to further dilute the Pyrethrin 0.01% and Canola Oil 1% by at least 100-fold. ...

Nope. The RTUs are required to be venturi type and can't approach that rate. Further, to be qualified for retail sale in California the instructions on the labels of the RTU and concentrate must deliver the same dosage for any listed application.

[b54red]

I have had the best luck with using a combination of an Insect Growth Regulator, Pyrethrim, and soap. One application is not enough and it needs to be followed up with second spraying 3 to 4 days later. The poison immediately reduces the population and the soap is needed to penetrate the webbing under the leaves as well as killing some of the mites. The IGR affects reproduction of the mites and works for quite a while. The problem with mites is when the weather is hot and dry they will come back eventually so you have to keep an eye out for them constantly. I have been fighting them for a month and they came on very suddenly in huge numbers like I have never seen before. I was able to control them but not before they seriously damaged a good number of plants.

Oil sprays work great on spider mites but are dangerous to use when it is very hot and that is usually when the mites are at their worst. I spayed my plants last night with a horticultural oil because it was due to rain starting this morning and luckily it did or I would have had to be out there trying to wash it off before it got too hot and sunny.

I am planning on setting out fall plants in a week or two. I almost always set out fall plants and the newer plants don't usually get the spider mites and if you watch them close and treat them before the mites can do any damage they are not usually a problem for fall plants unless you set out a new plant right next to an old infested plant.

Bill

[peebee]

Well I took cuttings of some healthy plants in the front garden, and am in the process of cleaning out my back garden now, almost done. It felt weird; it's the first time in my life I am removing tomato plants this early and without harvesting hardly anything at all. Pretty sad, actually.
Went to 3 nurseries and came back with a lone Black Prince seedling. Hopefully my cuttings will come thru for me.
Hermitian, my bottle of RTU is just a spray bottle to be used directly on plants, I don't see where it can be used with a hose at all; there in no nozzle thingy, only the lone spray, like any plain bottle of Windex, for example. So I don't understand what you said. Perhaps there are bottles of such insecticides that can be attached to hoses, like those Miracle Grow canisters? But then would they really be RTU? I thought RTU means you just spray, nothing to tinker with or measure? Ahhhhh, I'll be so glad when/if the spider mites are gone. I'll take flea beetles anytime, I actually miss them!

[JamesL]

Peebee,
You have it right. RTU is premixed, nothing to do but spray. Hose end spray is a concentrate and is usually labeled either just that- hose end or RTS - ready to spray.
Good luck!

[rnewste]

To my point in the above post.

If you further diluted the percentages in peebee's RTU bottle via garden hose application, you would have at least a 100-fold dilution of the critical ingredients versus the one ounce to one gallon ratio of the bottle I showed above containing 0.5% pyrethrin and 89.5% canola oil. You might as well just use the hose alone and try to blow them off.

The only application method that is effective is via a pump sprayer for heavy infestitations as peebee has. The RTU applicator may be fine for "spot" application - but you need to use the real deal if you're going to completely get rid of them.

Raybo

[Hermitian]

I like the hose-end sprayers with adjustable calibration. Just pour the concentrate in the canister, set the dial to the dosage and spray, then pour any unused concentrate back in the bottle. No mixing, no pumping, and very little waste.

As for the concentration of the 0.01% RTU vs. the 0.5% concentrate: the mixing instructions for the concentrate are 2 to 4 teaspoons per quart, with 2 teaspoons / quart recommended for mites. There are 192 teaspoons per quart.

0.5% * 2/192 = 0.0052%.
0.5% * 4/192 = 0.01%.

It seems that using the concentrate at higher dosage is equivalent to the RTU.

[Sun City Linda]

I have used the Take Down concentrate pretty effectively against spider mites and also Tomoto Russet Mites. I also keep powdered sulfur handy and apply it as a powder in the evening up the middle of my plants to get the leaf undersides.