Diatomaceous Earth

[Slap]

Wait until your soil is a little dry on top. F soil is to wet, the D. E will absorb and turn to a silaca and won't work for insects. If using to aide with healthy root system, my impression is to sprinkle on top of soil, water as usual. I mix it around a bit with my fingers so it isn't just sitting on top of soil, when not using for insects. I haven't had to use on cannabis for insects, fingers crossed, but me tomato's I have and it works. Messy though. Make sure it is FOOD GRADE, very important.

 

[Slap]

Downside if using for insects that I don't like is Everytime u water u have to use again if insects come back. I don't know if to much of a good thing will be a problem in the soil. Plus it's messy as all get go.

 

[Glassdub]

Wait until your soil is a little dry on top. F soil is to wet, the D. E will absorb and turn to a silaca and won't work for insects. If using to aide with healthy root system, my impression is to sprinkle on top of soil, water as usual. I mix it around a bit with my fingers so it isn't just sitting on top of soil, when not using for insects. I haven't had to use on cannabis for insects, fingers crossed, but me tomato's I have and it works. Messy though. Make sure it is FOOD GRADE, very important.

Yeah it's food grade, ended up frosting the surface about a 1/4", don't currently have have a pest problem, just recovering from an rookie overfeed, the duster was a mess ended up using a 1/3 measuring cup to apply.

 

[Glassdub]

Downside if using for insects that I don't like is Everytime u water u have to use again if insects come back. I don't know if to much of a good thing will be a problem in the soil. Plus it's messy as all get go.

I know its runs alkaline, so I plan on watering straight on one plant with my usual dehumidifier runoff water that runs a bit acid at 4.8-5 & test the runoff.

 

[DreamsOfDiesel]

I'm getting ready to try DE too, heard somewhere later of perlite in bottom & on top helps with pest control as well & isn't as messy but havent tried that either

 

[Glassdub]

I'm getting ready to try DE too, heard somewhere later of perlite in bottom & on top helps with pest control as well & isn't as messy but havent tried that either

I didn't care for it, messy, mars drainage & really drives the pH up.

 

[DreamsOfDiesel]

I didn't care for it, messy, mars drainage & really drives the pH up.

DE? or perlite?

 

[Glassdub]

DE? or perlite?

DE, also only effective when dry.

 

[CosmoGrows]

I'm getting ready to try DE too, heard somewhere later of perlite in bottom & on top helps with pest control as well & isn't as messy but havent tried that either

My experience: I started to have a small cluster of fungus gnats. Nothing to crazy, but definitely wanted to get on it early. With a combination of DE and MicrobeLift BMC, and sticky traps obviously, i havent seen a new gnat in a month or so on the traps. i use DE every other watering and M. Lift BMC almost every watering.
Was just a small population, enough i saw them flying around inside the tent though.

So. Thats that as far as my pest experience with it. I like it personally, i use a very, very, small coating on top when i do use it. Literally just a top dressing amount, maybe even half that.

I especially use it on my flowering plants, as when in flower you want to limit the amount of things that go on your plants, so its a nice safe pesticide to use, in my opinion. I use food grade.

 

[deweylee]

Wow, im suprised no one has mentioned the dangers of DE. It is commonly used in pools as a compliment to the filters. It is, as i understand it, the skeletons of microorganisms. It is dangerous to your health, especially your lungs. If you decide to use this do so with a bit of caution and wear a mask. Breathing this stuff in is like breathing in miniature razor blades that will cut up your lungs. Like i said i have only used it with pools, but what i have used has been pure DE.

I breathed too much over time, I now have COPD!!! wear that mask when using it, it does work on bugs ektoskelatel system, cuts through & dries the bugs juice up!

 

[Slap]

I have been using it for a bit on other areas around house and for Silca in soil. I do use a mask, I read up on it and mask was recommended. How about when in flower? Is it a bad idea to use? You know how messy that stuff is and hard to control to hit leaves only.

 

[Slap]

This isn't pool grade D.E this is food grade. The stuff I use has no chemicals in it. D.E used for pools is different. Not good for lungs if prolonged use over time, if inhaled, will mess with your lungs. WHAT WOULD THE DIFFERENCE BE USING FOOD GRADE D.E. VS. B.T which is a pesticide.

 

[Sawbuck.]

Wow, im suprised no one has mentioned the dangers of DE. It is commonly used in pools as a compliment to the filters. It is, as i understand it, the skeletons of microorganisms. It is dangerous to your health, especially your lungs. If you decide to use this do so with a bit of caution and wear a mask. Breathing this stuff in is like breathing in miniature razor blades that will cut up your lungs. Like i said i have only used it with pools, but what i have used has been pure DE.

There are two types of DE, pool grade and food grade. Pool grade has 60-70% crystalline silica in it, which is the dangerous, bad kind to inhale. Food grade is much safer, having only 1% crystalline silica. Both are high in silica, though, just be careful not to inhale the pool grade type, particularly.

 

[Homesteader]

DE has its purpose but it isn't as effective as some say IMO. The dangerous stuff on your lungs is the more effective at killing bugs too. DE is great for my chickens. I mix feed grade in with sand for a bird mite killing dust bath for them. They love it. Not so much a fan for cannabis or soil pests though. Its not effective and just makes a sloppy caked mess.
Just my two cents.

Just bumping this old answer though.

There are three grades of DE (food grade, feed grade and filter grade). Any DE that is heated becomes crystalline and should be considered dangerous for lungs, this is what is sold at home depot under "concern and safer name brands" and should not be used. Food grade and feed grade DE are amphorous silica and contain less than 1% of crystalline silica which is milder and safer on the lungs but feed grade (and filter) contains arsenic and other heavies where as food grade are sourced from mines that don't have heavy metals.