I have always had a lot of trouble with scale on my sagos. As with most people I tried product after product with failure until I tried Takedown Garden Spray. That has works beautifully ever since. The price of it has gone up and up (like everything else) so I saw that the ingredients (at least the ones they mention) are canola oil and pyrethrins. I thought I'd be smart and buy some pyrethrin concentrate which I found much cheaper and mix it with canola oil, water, and dawn detergent. I used the maximum amount of pyrethrin concentrate in my mixture that was suggested (they gave a range). I shake it well frequently during spraying, but it's just not having the same effect as the Takedown. Here's my question for someone out there who may know something I don't: Why isn't it killing like the Takedown? Are there hidden ingredients that are actually doing the bulk of the work? I guess I'll just have to pay the inflated TD prices, but I'm curious why what I tried didn't work.

Did you use the same amount of Canola Oil (89.5%) as Take Down? There's no telling what the other 10% of ingredients are, one of those might make the difference how well it sticks to the plant possibly. Does your mix apply and adhere to the plants the same as the Take Down did?

I don't grow Sago Palm (Cycas revoluta) but you might want to try a horticultural oil to break down the scale shell.

I found a recipe for making your own at The Spruce, but it also says:

A homemade solution of pyrethrin pesticide has a shelf life of only 12 to 24 hours, so any that is leftover after application will need to be discarded. Thus, it's best to grind and mix the pesticide in relatively small amounts as you need it.

If it's not because of their recipe using crushed flower petals, maybe that's the only issue and that 10% includes some preservatives to make the shelf life longer?

Can I ask what pyrethrins product you bought? Who is the manufacturer?

Great answers! I didn't know that the mixture is possibly good only for a certain number of hours; that's definitely possible they use a preservative. Also my mixture was definitely not 90% canola. I didn't realize I need that much. I was afraid of suffocating the stomata. I made 2 liters of solution with 6 teaspoons of the pyrethrins, a cup of canola, a little dawn, and the rest was water, so I bet I do not have nearly enough canola in my solution. I agree that the horticultural oil is a better idea, I just had canola on hand at the time. For the person who askeed, Bonide pyretherine garden insect spray concentrate was what I used. These were all very thoughtful answers - I really didn't expect that! Thank you so much as it definitely sheds light on several possible reasons. What a great group of community members.

ckorr2018 said:Why isn't it killing like the Takedown? Are there hidden ingredients that are actually doing the bulk of the work?

It isn't Takedown, of course... it's your creation.
I suggest if Take Down is working, and you tried the active ingredient separately PER DIRECTIONS ON LABEL and they are not working- using Take Down is the best option.

It could be that:
1) the dosing ratios aren't correct in your initial mixing of the concentrate due to errors (edit*** this is the tricky part: it's percentages per the label are 'by weight' not 'by liquid volume.' If you use a measuring cup or spoon, you're mixing it incorrectly and will get percentages DIFFERENT than Takedown- you would need to weigh the ingredients with a scale. It's hard to duplicate a recipe when important mixing info is withheld from you.)
2) the dosing isn't correct in final spray application - I.E. the 'water to spray concentrate mix' ratio was wrong, or other spraying fails: wrong time of day, wrong season, not sufficient coverage, wrong pH of water, etc.
3) your versions of the two active ingredients may not be the same quality
4) there might be a preservative or spreader/sticker in that 'mystery' 10% of inert ingredients, making it longer lasting on the plant or helping it cover better
5) one or all of the EXTRA 24 ingredients you added that are not in Take Down might be reacting/interfering with its actions and effectiveness-

https://dawn-dish.com/en-us/ho...

Of course, be safe- for you and your neighbors, for the environment (the bees!) and for your plants. I do wish you luck, as pests hurting plants you love are no fun. Dish Soap is for dishes, not sagos!

National Pesticide Information Center said:
You found a pest around your home that you want to get rid of. You decide you want a quick, simple, and cheap solution.
...
But before you mix up a batch, ask whether it's "safe" and effective.
http://npic.orst.edu/pest/home...