Simple Guide to a Great Organic Soil Mix

Discussion in 'Growing Organic Marijuana' started by cripes0103, Aug 14, 2012.

  1. #1 cripes0103, Aug 14, 2012
    Last edited by a moderator: Aug 15, 2012
    Hey Blades,

    I’ve spent a lot of time looking through all the posts in this forum trying to build a great soil mix. I learned a lot from the stickies and from the “Soil Mixes - NO NUTES - WATER ONLY - POST THEM!” thread but found that once I put together my mix it had a lot of holes. Through the help of FunTimeGrowHap and LumperDawgz (as well as many others) I think I’ve come up with something good and its mostly thanks to these two posts by LD. I’ve added a few small edits myself to make things more understandable/concise but otherwise all credit goes to LD (and FunTimeGrowHap for showing me). I hope everyone finds this as helpful as I did.

    Basic Mix:

    “I would like to share the organic soil mix that I use for my MMJ garden. It's based on the 'LC Mix' that appears all over the web.

    I start of with Sunshine Organic Growers Mix which consists of 40% organic peat moss, 30% organic coir (washed and inoculated with trichoderma spores), 10% perlite, 10% vermiculite and 10% pumice (medium size). The reasons that all 3 are added by the manufacturer has to do with the CEC (cation exchange capacity) of these 3 aeration amendments. The soil is ph adjusted with dolomite lime and is treated with organic yucca extract as a wetting agent.

    This is a professional 'soilless mix' for the nursery plant industry. All of the products used are the best available.

    BTW - Sunshine Mix is manufactured by Sun Gro Horticulture which also manufactures Black Gold products (their consumer line) and some other products that appear at Home Depot and Loews, etc. Sunshine Mixes are generally available in the Western US and ProMix is manufactured and distributed in the Eastern US. There is no difference between the 2 products if you're comparing apples to apples.

    To the soil I add 25% organic compost, 1 cf. of pumice or rice hulls and that's the basic soil” ---Lumperdawgz

    I personally built my own base mix from 40% peat, 35% EWC and 25% perlite and I think it looks great. --- Cripes


    “I use 3 mixes to keep things straight in my old brain. They are as follows:

    1. Food Mix
    2. Fix-It Mix
    3. Mineral Mix

    Food Mix

    You want about 2 cups of your food mix - however you get there. You're going to use alfalfa meal, fish meal and bone meal (I’ve seen a lot of people recommend fish bone meal over regular bone meal --- Cripes). Mix up a large amount with equal parts (by volume and not by weight) and add 2 cups of this mix to your soil.

    If you were to decide that you wanted to add canola meal (aka rape seed meal), flax seed meal (aka linseed meal), et al. then add the same volume amount of this to your mix but you're still only going to use 2 cups of the final mix. The total amount that you want to use does not increase - you're simply making your Food Mix more diverse (a worthy goal, IMHO)

    Fix-It Mix

    You're using kelp meal and a combination of the neem and karanja meals. Again mix these in equal amounts (by volume) and add 1 - 1.5 cups of this mix to your potting soil. If you were to add crab meal (another good Fix-It component) you would still add the same amount even with the addition of another agent, i.e 1 - 1.5 cups. (I highly suggest you use crab meal, it can be used in place of dolomite or other pH balancers --- Cripes)

    Mineral Mix

    You're using Azomite and/or Green Sand (adding both improves diversity, but you only really need one --- Cripes) - mix these together like the other mixes and of this mix you'd want to add about 1 cup to your potting soil. If you were to add Limestone (or Oyster Shell Powder) and agricultural Gypsum (both available at Home Depot, BTW) you'd add these minerals by the same volume but you'd still only use 1 cup of however a diverse mix you might come up with.

    Glacial Rock Dust is different and its application rate is 1 cup to 1 c.f. of potting irrespective of the other minerals you decide to go with.

    All the amounts above on all of the mixes are for 1 c.f. of potting soil or 7.5 gallons (allegedly)" ---Lumperdawgz

  2. Here is the exact soil mix that I'll be using for the grow I'm currently working on:

    Base soil(5 cu/ft):
    2.2 cu/ft Peat
    1.5 cu/ft EWC
    1.3 cu/ft Perlite

    Food Mix:
    5/3 cup Fish Meal
    5/3 cup Alfalfa Meal
    5/3 cup Bone Meal

    Fix-it Mix:
    2.5 cup Neem Meal
    2.5 cup Karanja Meal
    2.5 cup Kelp Meal

    Mineral Mix:
    5 cup Glacial Rock Dust
    2.5 cup Azomite
    2.5 cup Greensand
    5 cup Dolomite Lime

    If I could go back and do it again I'd get fish bone meal instead of bone meal and I'd get crab meal instead of adding dolomite lime, but hindsight is always 20/20 and I'm happy with my mix regardless.

    Here's a couple pictures from 3-4 days after I mixed everything up, complete with a good amount of white fungus (signifying good microbial activity if I'm not mistaken):



    I'll update with a picture of what the soil mix looks like after a few weeks of cooking and mixing once I get home.
  3. Lookin' good cripes........that soil is livin' large! I think you're gonna have to start a grow journal.


  4. #4 cripes0103, Aug 15, 2012
    Last edited by a moderator: Aug 15, 2012
    Thanks Chunk, always feels great getting a compliment from someone as experienced as you! I actually do have a grow journal, you can check it out in my signature under "My 2012 all organic grow: Dream Queen"

    As promised, here's a picture of that same soil mix I made 3 weeks ago as it is today:

  5. #5 jerry111165, Aug 15, 2012
    Last edited by a moderator: Aug 15, 2012
    Cripes - is this your first organic soil mix, or first real attempt at organics? If the answer is yes, then fantastic job! It's a whole lot more rewarding when you mix your own than simply opening a bag, pouring it into your pot and planting into it. It also gives you an opportunity to tweak (as you see fit) as you start working with your soil.

    What is your compost/humus component?

    Again, fantastic job.


    Edit: ps - with stuff like the crab meal, it's simple enough to top dress and work it in a little bit if you find you want it in there.
  6. #6 cripes0103, Aug 15, 2012
    Last edited by a moderator: Aug 15, 2012
    This will be my first time building my own soil mix. Previously I have bought either FFOF or Roots Organic soil and fed my plants with Botanicare PBP nutes. I've had some great results but I'm looking forward to seing what this all organic business can do for me.

    The compost/humus component I used in this mix was store bought EWC. In the future I plan to make my own castings but for the time being I'm forced to source them locally.
  7. #7 geneween77, Aug 15, 2012
    Last edited by a moderator: Aug 15, 2012
    I like your summation of LD's post, I just built my first soil last week and spent weeks trying to get a good grasp of the process this is a nice beginners guide. I can't wait to see the difference, I was using FFOF and FF nutes.

    Just got some Neem seed meal and crab meal in today so I added it into my mix, I hope it being a week behind wont be a problem.

    Now I have to really figure out a tea i want to use. I just found a local place that makes some organic AACT, but I think I just might try it myself.

  8. Start with quality compost, vermicompost or earthworm castings - several cups in a 5 gallon bucket. Fill with room temp, chlorine free water. Add 2 tablespoons of organic blackstrap molasses. Aerate the living hell out of it for 36 hours.

    Apply both root drench, and strain for foliar spraying.

    To hell with paying for ACT. A strong air pump is a must.

    Good luck!

  9. That's what I have to get next, still trying to sort out my best yet economical option. The rest of the stuff I already have.
  10. Hey Cripes,
    I had a question on the recipe you posted.
    The particular Recipe with the "fix-It" "food mix" was PM to another member that decided to post for help( at least that is what i gathered from reading through all the ld soil mixes)
    its a little confusing though compared to the other 3 LD recipes.

    In 2009 he used a lot of seed meals and used about 2 cups of amends. per cu.foot. , and 5 cups of gai rock dust. "The basic soil recipe of mine " thread is what im referring to.

    then updated recipe 2010/2011 was basically a kelp/neem/crab equal parts and sill same amount of rock dust.

    i was wondering why this particular recipe has 3.5 cups of amendments and 1 cup of rock dust.. and in every other LD recipes he would use equal amounts of amendments and heavy amount of gai rockdust

    When in past posts LD said 4-5 cups of gai rock dust independent of other mineral mix
    and the 3.5 cups per cu. foot of amendments in unequal parts is only in the "food-mix, fix it mix" recipe that was PM'd to another member.

    just about to mix a new batch of soil , And i have been debating over the exact recipe you posted.
  11. I honestly wish I could answer this question for you... I think someone with a lot more research under their belt would be better able to answer it (maybe someone like Chunk?). The research I've done so far has been, frankly, kinda lazy. I've been looking up what to add to my soil and kinda skipped the chapter on why. You asking that question really made that apparent to me right now, haha.

    I hope someone else can answer this question more effectively, anyone want to weigh in?
  12. Can't say regarding the amendments, but as far as the Gaia glacial rock dust, it's still 4-5 cups per cubic foot. Just make sure that you are well aerated and you'll be fine.

    Glacial rock dust - not Azomite or any other kind/brand of volcanic clay, but GRD.

    There is a difference.


  13. Hey Jerry, glad to hear you chime in. In the post that Hap shared with me, which was originally written by LD, it says 1 cup of GRD per cf. Do you think that was just a typo?
  14. Hi Jerry:wave:
    I am trying gro-stones for an aeration for the first time. looks like pumice made out of glass(no its not sharp) , it is not dusty like perlit,e but one should still wear a mask when handling it and rinse it outside with a gardenhose before using (you can do this in the bag.)
    I picked up the Vitalearth glacial rock dust hopefully it's on par with Gaia Rock Dust.

    Can you help me with a link to your soil construct, I've gone through the organic obsession thread many many many many many many times but couldnt pinpoint your soil build.

    I am trying to mimic your No-Till method, and thanks for all the info you've shared. I know its really helped me out :smoke:
  15. #17 jerry111165, Aug 18, 2012
    Last edited by a moderator: Aug 18, 2012
    Unless it was, perhaps, an old one? I'm not sure pal - but I do know that for a long time now he has been prompting the 4-5 cups/CF, and I don't think that has changed.

    Aeration is important.

    Cripes, I have been trying lately to learn more about rock dust and it's uses. We all need to continue to try and learn!

    I can't take actual credit nor do I want to, but this is a (very) brief rundown on WHY. Please bear with me - this is a lot for my stonefish brain to try and explain.

    Soil, in it's most basic form: humus - ie: composted, or rotted plants, trees, leaves, grass, etc, plus animal waste, bodies, bones, and shattered, broken, pulverized rocks. IE: ROCK DUST. That's it - those 3 items are what comprise soil. Anything in the world can fit into those 2 categories - humus and rock dust! The Earth started out as a big rock. Over time, the most basic of (plant) life, algae, grew on this rock and started breaking the rocks down. Still more time progressed as slightly more advanced plants started growing in the rock dust created by algae, these plants broke down and humus was created, thus making it possible for even more advanced plants to live and die in what was now soil - humus and rock dust (shattered rock). The rest is history.

    Mineral - basically, laymans term for an element that can be mined from shattered/broken rock. There are 83 elements required for plant health. Where do all of these different elements come from?

    Rock dust in soil provides "anchors" for fungi and bacteria (soil microbes) to attach to. It provides soil structure and provides pathways for air (oxygen) and water to pass through.

    By bacteria attaching to and surrounding different pieces (different minerals, different elements) of shattered rock, they begin to break down the rock, which takes years and years. But, while they surround different minerals (elements) they create different enzymes that do all kinds of different important things - a biggie being that they are a key component in nutrient cycling - which, of course, helps provide the elements required for plant health! So while we may not use rock dusts directly for their direct mineral content, the enzymes created by the bacteria and fungi attaching/anchoring themselves to the rock dust indirectly help nutrient cycle different elements from different sources - such as kelp meal, for example. So indirectly, (very indirectly), the rock dusts used help to provide the 83 elements needed - from different sources. But this is only one benefit of enzymes - there are obviously many more.

    All plants require and hold these 83 elements - and some hold them better than others. Some hold different elements better than others - hence, this is why we utilize assorted "dynamic accumulators". Kelp and alfalfa are key examples.

    It's hard to explain when you're (I'm) still trying to wrap my own brain around it....*lol* did any of that make sense?

    Rock dust - very important. Essential.
    Soil - humus & rock dust.

  16. So if I'm not mistaken if I were to use bottled nutes with soil I only need to make a base soil ay? Promix, perlite, dolomite lime and coco? I used shit soil in my last grow and my plants suffered a lot through veg but I'm just trying to get things straight before I start any more seeds. 5 weeks in and my plants are only 5-6 inches tall with fan leaves smaller than my palm. Oh well. You live and you learn. Thanks looking out. Any advice or recipes much appreciated.
  17. Yes, you can.
    The basic mix I've used for years is nothing more than peat, perlite, pine bark mulch and dolomite lime. This worked great with Jack's Classic for close to 35 years.
    Add a few amendments and EWC to this (more or less), and you have the organic mix that I've been using for the last 5 years.
    But the basic mix hasn't changed in 40 years or so.

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