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Diotomaceous Earth & Pests

I have a baker’s dozen clones at about a month old, some of which came off of a plant found to have Thrips. I see marks on some of the leaves of the clones so I’m using Diotomaceous earth sprinkled lightly on top of them. Most thrips stay underneath–that’s where I’ve seen 2 of them on the ‘mother’ plant. But it may still work & the silica is like a nice soil additive for the soil below.

Thoughts or tips? I’m sure others must be using DE for other pests.

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Be careful with DE, it threw our Cal/mag way out of whack. We used it for months and months before I started to see the problem in our soil.

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Did you find a solution that worked equally as well, without the problem?

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yes, we started spraying twice a week ,lol. I have not seen a single thrip, aphid, or evenagnat since we started biweekly spraying.

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if you don’t mind, what are you spraying with? If you don’t want to share I totally understand.

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Are there variations in quality of DE? Just had a thought on that while looking at this. $1 bag of soil versus brand name might give different results, you know? I buy my personal DE from Home Depot, for example :rofl:

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I rotate my sprays in order and spray twice a week. knock down with Pyganic( have to stop using now because of new Cali regs), but switching to an edible essential oil spray.
Then PFR97, Botaniguard, and finish up with Grandivo. rinse repeat.

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Iam assuming the quality varies , no hard evidence or tests .

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Would that help against grasshoppers at all? We have horrible, horrible hoppers out here. Looked at some stuff called Nolo that is supposed to be a generational killer. The other one are these yellow moths/worms that like to eat out the buds. I’ve never seen so much bud weight laying on the ground before until I moved to SE Colorado and saw how insects can ravage plants here.

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There are MANY different grades of DE. @mwmzx6 If you weren’t using a natural grade, that could be the reason why… For example, maybe you used a processed and purified Flux-Calcined Grade meant for filtration industrial filtration vs. a Natural Grade.

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Yes so there is food grade DE and that’s what I’m currently using because it’s what I have on hand. (I’m currently on day 11 of 1 tsp DE taken in water for my health.) In researching, I’ve found that there definitely is industrial grade DE and one woman who did a podcast had both on hand. She had called the distributor to ask how much quality difference there was. The industrial is a lot more coarse & that’s about it. This woman ends up blending the industrial to use for things like topical applications and bug/pest prevention but never uses it internally.

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Just to clarify: “food grade” meets the standards necessary for filtration of consumable products. I would be prudent when it comes to retrieving your information. We wrote a blog on this topic earlier in the year - we are one of only a few Diatomaceous Earth suppliers in North America.

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Very cool, thank you for sharing the information!

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DE works by scraping the bellies of bugs which leads to death for obvious reasons. It’s ground up ancient aquatic organisms & so under magnification you can see that the particles are sharp-edged. So I would think it would work for grasshoppers if you have enough in and around areas that they frequent since they do move in other ways other than jumping.

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This woman had spoken to one of the other two suppliers who said they go through the industrial DE very quickly. They said that due to the fact that they personally store the industrial DE outside in a pile, there is the chance of bird droppings or other foreign material contamination. But they also stated that they go through it so quickly it wouldn’t have much time to collect.

What is supply of DE like? I wonder how much effort the legal Cannabis growers have looked into it as a safe pest deterrent vs pesticides.

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Dan, It sounds like she is referring to a stockpile. This is where mining companies literally stock piles of crude diatomite ore prior to processing. Contamination cannot occur as a direct result of calcining and following by processing the ore into Diatomaceous Earth. The only possible contamination is in biological/mineral form.

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