Here is a guide on building your own super soil. This recipe was put together by @TempleGrower, who is a member of our cannabis growers forum.

If you are thinking about building your own living soil, feel free to ask for advice in our cannabis growers forum

TempleGrower’s Organic Super Soil Recipe

VicHighSoilMixes, Organic Super Soil Recipe

Vic High’s Recipes

This is my general ‘super-soil’ recipe that I’ve been using in my indoor gardens for a few years now with very excellent results.

Being that my job can take me away for weeks at a time, I’ve tried to find/come up with something that is basically self sufficient from seedling to harvest, with the only addition being some high quality 6.5-7.0 pH H2O. The basic recipe I started with was Vic High’s Soil Mix #2, but I’ve since tweaked and substituted some of the amounts/ingredients. If you search for either ‘Vic High Soil Mix’ and/or ‘Subcool Supersoil’ on Google, there is a lot more info and background for anyone interested. But just so everyone knows, I didn’t come up with this recipe; just amended it for my local inputs. Full credit to Vic High and Subcool (RIP).

It’s up to you what you like to use but, I try to stick with stuff as local as I can get it, and especially if you can make it yourself (e.g. compost, worm castings, potentially manure, etc.). I live in Saskatchewan so, the stores I use to source ingredients from are Peavey Mart, Home Hardware, Canadian Tire, Home Depot, Costco, etc., but preferably local garden shops/local farmers.

My amended version is as follows:

105L high quality potting soil 

  • Primary medium – Any good quality potting soil will do – I’ll usually use either the Costco bails (‘The Answer’ – good value @ 12.99/85L, but only available in spring/summer. Made from peat moss/perlite/composted wood bark*), or the blend from Early’s Farm and Garden (more money @ $9.99/55L but always available, and local. Made from peat moss/vermiculite/perlite/loam.) Whatever you like/have available will likely be fine though. Just ensure it’s not ‘pre-amended’ with added fertilizers or water-holding crystals or things like that.

10-15L of worm castings 

  • N-P-K (trace – depends what the worms ate)/Micronutrients/Microbes/Moisture retention – I use either the Mark’s Choice brand from Home Hardware or the local garden store house brand. This is something you can definitely make yourself though through vermicomposting your kitchen waste. Don’t over-do these though, as they can cause issues with drainage.

3 cups blood meal 

  • Nitrogen – N-P-K ratio is 12-0-0, and the N is readily available. 

6 cups 1/2 Blood + 1/2 Bone Meal

  • Phosphorus – N-P-K ratio is 4-10-0, and P is also readily available. Some N in there too. 

3 cups dolomitic lime 

  • Calcium + Magnesium – Plants need Ca and Mg for vital plant processes. Also important as it helps to keep the soil from becoming too acidic by acting as a buffer as Ca- and Mg-bearing compounds react readily with acids, helping to protect the medium’s pH from large swings due to inconsistent water quality, weird soil, experimental amendments, etc.

1 heaping cup of Epsom salts

  • Magnesium/Sulfur – Not much to say here but, very important. You can get this from the garden stores, or buy the big jug from WalMart/Costco/etc. Just be sure it is unscented – it should be pure Magnesium Sulphate (MgSO4) with no additives.

5-10L Perlite/Vermiculite (or more if you prefer)

  • Drainage – Most mediums have some perlite/vermiculite already mixed in but, not enough for the amount of extra organic material added to this mix. I personally always have used perlite as vermiculite has, in the past, been associated with asbestos (the mines where the mineral (called mica) that vermiculite is made from can also host asbestos-bearing minerals). I don’t think this is an issue anymore, but best to err on the side of caution, in my opinion. 

5 heaping spade-fuls of sifted compost OR ½ bag (8-10L) store bought compost/steer/sheep manure 

  • Water retention/drainage/microbes/Macro & micronutrients – Garden compost is amazing stuff. It promotes proper and even drainage but at the same time helps with water retention (makes sense right? ?) . It’s also LOADED with beneficial microbes/fungi/etc., which help the plants absorb all the delicious treats you’ve added. I make all my own compost at home, but if you aren’t able, try to find a neighbour/friend/generous green soul who might donate some. It’s usually available at the garden shops as well. One thing to note is if it’s homemade (even if it isn’t), you may get some easily plucked weeds (which can then be composted!). You might also bring in some pests (insects and/or their eggs,mainly) which could prove to be more of a hassle than it’s worth in the end. Compost’s NPK content can be difficult to dial in between batches too, so it’s sometimes hard to keep a consistent profile. An excellent alternative, and my personal choice for making soil for an indoor grow is manure. I have used both steer and sheep manure instead of compost with very good results. Watch though – these manures tend to be fairly dense and have a relatively high moisture content, and so don’t promote drainage as well. They are an excellent choice though, and are usually very cheap and available.

 

And that’s it! Mix it all up nice and evenly, moisten (a good 4-6 L of CLEAN, chlorine-free water is usually lots), cover and let sit (also known as cooking – I use a 60 gallon drum for this) for a minimum of 1-2 weeks but preferably 3-4, mixing and turning occasionally. I like to use a kiddie pool, dump all my ingredients in, and mix it up with a rake. Saves a lot of mess, and you can usually get everything blended quite well. After mixing, I transfer it all to the 60 gallon drum and put the lid on. Every couple days I open it to refresh the air, as well lay the drum on it’s side (with the lid on, obviously) and roll it around to mix up the ingredients until the 3-4 weeks are complete. It’s important to blend very well in order to avoid ‘hot spots’ due to clumping of ingredients.

I usually grow in 3 gallon pots filled approximately 2-3 inches (5-8cm) from the top, and my plants are always happy from day 1 straight through to harvest (regular/feminized plants usually grow vegetatively for 4-6 weeks, flower for 8-10 weeks and/or autos run from 90-120 days, seed to chop). I can usually get about 20 x 3 gallon pots worth per batch, which usually lasts me for the whole year. It’s quite cost-effective at ~$30-50 per drum or close to about $3/pot. I use it to start my seedlings in as well. And obviously, you can use this mix for any plant you want to grow, not just Cannabis. I have a 4 year old Aloe plant that absolutely loves it…

I should add that during the grow I do add liquid kelp fertilizer to the irrigation water once per week, and a locally made compost tea called EPSI. once every two weeks. I also inoculate the soil with mycorrhizal fungi when planting/transplanting. These aren’t necessary if you can’t get your hands on them, but are very nice to have. Besides that though, no additional nutrients needed. Just properly pH adjusted water (6.5-7.0 pH) and a grower’s love. If you do have a deficiency (Mg is the most common I’ve run into if something does occur), topdressing the soil  with the appropriate fertilizer and watering it in is all that’s required.

And remember to find the best value for your money when sourcing these ingredients as well – buying bulk is always cheaper, and bone meal, blood meal, perlite, epsom salts, and dolomitic lime can all be preserved basically indefinitely, if kept moisture free.

If these ingredients are not available to you, or you want to use something else, this is a link to a list of some alternative options. Even if you do have everything listed above, it’s worth having a look at. Just ensure whatever you decide to use provides close to the same amount of whatever nutrient you are replacing. The link is: 

https://extension.oregonstate.edu/sites/default/files/documents/1/lc437organicfertilizersvaluesrev.pdf

Also, here is a very short, but excellent article regarding these organic inputs we are focusing on in this soil mix, for anyone interested:

https://extension.oregonstate.edu/news/heres-scoop-chemical-organic-fertilizers

And, if you really want to delve deep into the very interesting science of soil microbiology and the soil food web, I highly recommend checking out this link from the brilliant Elaine Ingham:

Soil Biology Primer – Elaine Ingham

*About using wood bark or composted-wood based-soils (like ‘The Answer’ brand I mentioned before) is that if the wood hasn’t fully decomposed, it can actually rob the soil of nitrogen to help to continue this decomposition so, make sure that your soil is fully soil without big chunks. I’ve never had an issue personally with this but, it is a thing, so be wary.*

Enjoy! I hope this works as well for you as it has for me!

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Ingredients. (Dolomitic lime missing)

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1/2 the Soil

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1/2 Epsom Salts + 1/2 Dolo Lime

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1/2 Blood + 1/2 Bone Meal

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1/2 Worm Castings

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1/2 Perlite

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All manure

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Rest of Perlite

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Rest of soil + worm castings

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Nicely mixed using garden rake

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Evenly distributed ingredients

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Moistening the soil (1 capful of EPSI compost tea added as well)

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Transferred to drum

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Drum sealed up

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Drum ready to roll

12 Comments
  1. @sydarko
    Hey there again. Yes, you can use it right from the get-go – no mixing or diluting necessary. If you did want to mix in some regular potting soil to start your seedlings in, you absolutely can and shouldn’t run into any issues. Just ensure you use the full strength soil in whatever pot you transplant the seedling into to finish in.
    For your second question, that would depend on how long you decide to grow your plants. I designed the soil to be able to go through 3-3.5 months of growth in 3 gallon pots without having to amend them during the grow, save for a weekly shot of 0.1/0.1/0.5 liquid kelp and home made compost tea (if you have it). That’s more for the microbes though. Occasionally I do run into some deficiency issues depending on the cultivar I am running (some are hungrier than others), but all I use to fix any issues like that is a bit of fish emulsion, usually around 4/4/3 or thereabouts. If you wanted to use bigger pots with more soil, you definitely could. I’m just not sure how long you could go in a 5 or 7 gallon pot, for example, before running low on food, as I only ever have used 3 gallon (or smaller) pots.
    Feel free to tweak the recipe but if you get too much of something in a supersoil, it’s not nearly as easy to remove it as it is in coco/hydro-style grows. For most nutrients, once they’re in there, they’re in there for good. I’d suggest amending as you go along, but only if you need to. With proper watering (i.e., keep the medium moist/damp – not sopping, but not dried out. Microbes need moisture to do what they do), you shouldn’t have too many issues to worry about.
     

  2. Hey again
    So after it’s cocked and ready to go, do you use It solely in the pot or you mix it/level with regular poting soil?
    Also, I know you mentioned it but what if I’ll use only plain ph’d water for irrigation without never top dressing it, will it work good? Can I maybe make the super soil a bit stronger instead ? Thanks in advanced !

  3. @sydarko
    Hey thanks for pointing that out! I’ve edited it now but it should have said 6 cups of pure bone meal. I have no idea how the ‘1/2 blood meal’ bit got in there… web-gremlins perhaps. 😎 
    But yes, hope that clears it up, and thanks again for the heads up!

  4. A must try indeed. Thanks for sharing. 

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    @sydarko TG will be on later to answer this mate 🙂 He will know 

  6. Hey there
    Something is not so clear to me on the ingredient list, there is 3 cups blood meal. That I understand, but after that there is 6 cups 1/2 blood + 1/2 bone… can you be more specific on this please? You mean 3 cups of each blood and bone meal? I want to try it and want to follow it to spec (:
    Thanks in advance

  7. I just read this after your harvest weight contest…Should not have doubted you, haha what a fool I am to guess such a low number. Thank you for sharing the work, this should help with my yields!

  8. I’ve given the recipe a teeny little update, mostly to do with compost/manure as well as some new pics detailing the mixing and blending process. They look a bit wanked but, maybe it’s just my computer? Do they look all over the place for anyone else?
    And I’ve removed the ‘organic’ label from the title as this word is a bit of a misnomer most of the time, and unless you buy all organic inputs, the mix won’t necessarily be officially ‘organic’, whatever that really means. I realize it still says it pretty boldly in the title picture, but that will hopefully be changed at some point as well.. ?.
    I’ve also added a new link to a huge article all about soil biology/microbiology – basically the theory that comes into consideration when developing these soil blends and keeping them healthy. It’s written by one of the gurus, if not the top soil lady of them all, Elaine Ingham. Definitely worth a download if you have the time/interest to go through it.

  9. @grower-urbanShit, sorry man, I did NOT see this question until now, lmao.IME, salt-based nutes (for example, and god forbid, MiracleGro, lol) are not good for a living soil. Those nutes are in a form already available to the plants, so the microbes aren’t really necessary doing anything helpful.. and I’ve never looked myself but, I have read that such a heavy salt load is quite detrimental to the little things living in the soil. I would think it would fry them pretty good…I see it like ‘plant foie gras’ tho – with bottled nutes, you’re basically force feeding her as much as possible to get the fattest buds. With the microbes, the plant has a chance to sit and enjoy her meal, taking what she wants when she wants.

  10. ?? Will definitely try this on next year’s outdoor and soon on my indoor (still have coco and non-organic salt based nutes to use up).

    Question: what if I use salt based nutes on a living soil? Will it be too much for the plants? Will the synthetic nutes kill the microbes or beneficial fungi/bacteria? Is liquid organic nutes ok to use?

    Love the idea of nature taking care of nature but sick of learning by error, any info would be much appreciated.

  11. Here’s a bit more to add on:A very good explainer regarding organically derived fertilizers like the ones use in this recipeA list of some other options if you aren’t able to source certain ingredients locally.

  12. This is TG guide to making living soil. It was written on the front end of the site, but not crossed over to the forum… so here it is 🙂 

    Quality post TG. 

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