Diatomaceous Earth Powder and living soil mix - need advice

I’m getting ready for my 2nd indoor crop of autoflowers (Runtz this time) in a 2x4 tent with HYDRO PLANET T5 2x8 6500K lights to start and then HLG 260XL Rspec with an additional HLG 135 Rspec in center. I want to try using living soil. I am looking to use Diatomaceous Earth in the mix. Please see my soil mix below and advise.

My purposed mix:
3 parts potting soil
1 part coco
1 part compost
1 part perlite
Worm casing - not sure of the amount
coffee grounds -yes\no\maybe?
Diatomaceous Earth Powder - 1/4 cup per cubic yard (read this somewhere)

Help me buds!
@BudzMS @Newt @beachglass @CurrDogg420 @new2-420 @noddykitty1 @Flitme @Mhcnola @CatDadPower


Be careful when you choose. Stay away from anything that say “feeds for _ months.” Honestly, you’d be better off buying a prepared soil intended for cannabis that is buffered for cannabis.

Coco and soil grows are managed differently. Not really a good idea to mix them. If you go with your recipe, then I would replace coco with peat.

Your lighting is in good shape.

Happy growing.

DE is generally used as a top cover if facing pest problems. It does contain silica, which is a helpful supplement given during waterings.


I am using this potting soil. It does say feeds for months but I did let it sit for 1 year before using. not sure if that helps or not.

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Doesn’t help if has been sitting. It’s not a good cannabis soil. It will nuke your plants with nutes and submarine your pH every time you water.

Also avoid any soil that says “moisture control.” Cannabis needs wet/dry cycles.


What about in between grows?

And this one…

Living soil stays moist. If it dries the good guys die. Personally I would buy an ammendment like Earth Dust and some organic non ammended or lightly ammended soil. After a few weeks of “cooking” you plant. Ammend 1 more time at flower with a boost provided for auto. Water only in between. No ph adjustment necessary if water in a range of 5.5-9 or so. I use ED exclusively now with fantastic results. Also soil is reused and improves every time.


I’d likely start with something like ProMix HP as your potting soil if you want to start with a nearly inert medium. Good luck!


I thought Diatomaceous Earth Powder was ED?

So add ED again?

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No. Earth Dust is a living soil ammendment. Treat soil…grow…top dress at flower…finish. water only besides that. DE is silica. For a new living soil person the living soil kits are fantastic.


I use granular Diatomaceous Earth (Autozone Floor Dry) in all of my potting mixes in lieu of perlite. I prefer it to perlite for drainage because it also holds water.

I am new to indoor weed growing so I am just relating what I do and not suggesting its use for growing marijuana.

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I would personally never mix coco and soil as one medium requires flushing from excess salt buildup, the other does not. Additionally, both mediums regulate pH differently. I’d stick to happy frog, personally, and a mile away from standard store bought potting soils, but that’s me. If I’ve learned anything about this hobby its that there’s a million ways to do it.

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Which requires which?

Is happy frog a living soil?
Do you have pros and co s either way?

Coco requires flushing, soil does not.

Happy frog is organically amended, as is ocean forest. The only difference is that the latter of the two is much more fortified with nutrients.

I’m not an organic grower, but if you’re absolutely dead set on it Amazon sells organic living soil concentrate. The bags run around 40 bucks and provide organic nutrients for the entire grow (allegedly). They have thousands of great reviews on Amazon and it takes all the guess work out of measuring every individual amendment you’d have to use in your own living soil. If memory serves, one bag of concentrate feeds four 5-gallon pots.

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Adding @latewood

Here is what I got today for a soil base. Hopefully I can get some suggestions for a mix.

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@Storm @zeuspaul @Newt @CatDadPower

Please see above

If this is all you have, I think you are still underprepared for your grow and will be nutrient deficient rather quickly. Bat guano and earthworm castings do not provide the matrix of macro and micronutrients alone. ProMix is inert and the potting soil will last 1-2 two months tops before needing refeed or progressive transplant into amended soil. My recommendation would be adding bottled botrients to regiment to cover your P, K, and micro needs. Not to mention cal mag for the entire grow until week 3 of flower and mag sulfur from then to finish. I don’t want to be a letdown, but I want to make sure you are prepared and aren’t met with disappointment later down the line. If you’re worried about bottled nutrients killing your microbiome or ruining your organic grow, just be aware that there is no science that supports this. It’s an old stoner myth seeing as even organic matter breaks down into… the same salt compounds that disassociate into the ions roots can use.

Sorry. I’ve never built a soil.

I also have compost to add and cal\mag, The container just fell off the stack.
I’m not really looking for organic but I soil that should not require a lot of additional nutes during the grow until flower.

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