BUDGET soil mix for 100 gallons?

SG420

Active Member
Planning on growing 5 plants each in 20 gallon smart pots. (100 gallons soil needed) With that being said, what is the cheapest recipe/way to go about this? I should also mention I haven't ever grown cannabis and this will be my first time doing so. Organics is pretty overwhelming for a beginner like myself. (npk ratios, amendment ratios, compost teas, 2 parts this 1 parts that etc) I just want to keep things at a bare minimum that will still produce nice smokable buds. Could anyone please provide me with a cheap beginner/fool proof recipe that doesn't require a billion amendments and will show nice results. Thank you all in advance.
 

ShLUbY

Well-Known Member
Planning on growing 5 plants each in 20 gallon smart pots. (100 gallons soil needed) With that being said, what is the cheapest recipe/way to go about this? I should also mention I haven't ever grown cannabis and this will be my first time doing so. Organics is pretty overwhelming for a beginner like myself. (npk ratios, amendment ratios, compost teas, 2 parts this 1 parts that etc) I just want to keep things at a bare minimum that will still produce nice smokable buds. Could anyone please provide me with a cheap beginner/fool proof recipe that doesn't require a billion amendments and will show nice results. Thank you all in advance.
define cheap
 

SG420

Active Member
define cheap
like 100$ total (not sure how realistic this is. i just don't want to be ordering soil online having to spend an extra 80$ for shipping etc. id like a reasonable soil recipe beginner organic friendly that will provide good nutrients to my plants and doesn't require me having to buy a bag of 20 amendments etc
 

ShLUbY

Well-Known Member
like 100$ total (not sure how realistic this is. i just don't want to be ordering soil online having to spend an extra 80$ for shipping etc. id like a reasonable soil recipe beginner organic friendly that will provide good nutrients to my plants and doesn't require me having to buy a bag of 20 amendments etc
probably not gonna happen for 100$ unless you are extremely resourceful, and I'm not sure what area of the planet you are from so I don't know what is locally available to you. besides, if you're looking for high quality flowers, cost shouldn't be your focus because the end product is worth far more than what you are going to invest. Please don't devalue a quality product with the mindset of a dollar. We've done it with everything: food, art, music, etc. I'm not saying this to be a dick, I'm just saying it to draw attention to how our culture has shifted in the wrong direction :) . Oh and you're never going to get around having to measure things out and follow a recipe if you're looking to build a soil, so come to terms with that. it's not difficult. anyone can follow a recipe.

first thing, you need sphagnum peat moss. DO NOT buy the premixed stuff (contains perlite). You want the canadian sourced block of sphagnum peat moss, i wont go into the details of why as you are a novice so i'll spare you that.

second thing, you need QUALITY compost. no "mushroom" compost, no "municipal waste" compost. You want something that is going to contribute beneficial organisms to your soil. Worm Castings are a great source (though quality varies). Dairy Doo (if you're in the great lakes region) is a good source and not expensive. I'm going to assume you do not have your own homemade compost. Honestly this is the product that I would not skip out on cost.

third thing you need is drainage. i've heard people have access to 3/8" particle sized red lava rock from landscape supply companies. pumice can get expensive but is another good option if you can find it cheap. perlite... expensive and not worth it long term.

Lastly, some mineralization is pretty critical. rock dust is cheap, and sometimes can be sourced locally, especially on the west coast of the US.

These four things make up your base mix. roughly equal parts of peat(pre wetted) : compost : drainage (so that's 33gal:33gal:33gal) easy enough right? for 100 gallons of base, i would add about 10 cups of rock dust.

now for fertilizer, you can get away with an organic "all purpose" blend. for that much soil, you will need about 30-35 cups (so just say 2 gallons) worth of fertilizer (no i don't know how many lbs that will be). typically these all purpose ferts have a broad spectrum of things in them in terms of nutrition, and when i introduce people to organic growing, this is what I recommend to them.

you will also want to get some type of myco product, as cannabis performs better with endomycofungi (i know i get it you're a novice but it's easy to get). you just sprinkle it on the roots of the plant and that's it. you don't need to know the why, just know its beneficial.

mix everything up and add some moisture so that it is wet but not sitting in a puddle of water. loosely cover it (a large tarp works great) and once a week mix it up to introduce fresh air.
 

SG420

Active Member
Thank you so much for the in depth reply. A few follow up questions.

1. With canadian spagnum peat moss, is pH something I should be worried about? (This goes for the worm castings and other amendments as well)

2. With worm castings do I need to be worried about NPK values? If so then what is a good NPK value I should look for?

3. ^^ (Also you said worm castings were not something to cheap out on, with that being said is there a specific brand you would recommend that I would be able to get shipped from amazon or ebay?) I was wondering if this would be any good? https://www.horticulturesource.com/aurora-innovations-roots-organics-earth-worm-1-cu-ft-60-plt--p23716?gclid=CjwKCAiAyfvhBRBsEiwAe2t_i0OTzGVVTdAB1NC2jXi9iZkM3X3b60aFZyYVfg8Xb95EeqFTVc0ocxoCNcIQAvD_BwE

4. Reading from other users on here it seems the 3 most common used forms of rock dust are glacial, granite, and basalt. Which of these do you recommend the most? Or is there a different one thats less common but better?

5. You mentioned that the four amendments (peat, compost, drainage, minerals) make up your "base" When you say base what do you mean? (also you mention the peat should be "pre wetted" but then later you go on to say mix all the amendments and fertilizer together with some water. Could you elaborate on that some?

6. Fertilizer confuses the shit out of me. I have read that cannabis needs high N in the veg stage, and high P & K for flowering. So my logic is if the plants need high N in the veg stage, I would buy a fertilizer for veg, and then later on give the plants a different fertilizer for flowering? But you say to mix the all purpose fertilizer with everything the peat, compost, drainage, and minerals. So with you recommending an "All purpose organic fertilizer" would it cover veg and flowering without needing to have two types of fert one for veg one for flower?

7. For "All purpose organic fertilizer" what NPK should I look for? And to make things easier on me could you recommend or link an all purpose fertilizer?

8. Also you never mentioned anything about compost teas, foliar feeding, topdressing etc. I'm assuming an all purpose organic fertilizer mixed in with the peat, compost, drainage, and minerals will provide all the nutrients needed from veg to flowering with only water needed? No nutes from time to time?

9. Is it safe to start from seed in this recipe? Or will it burn the plants?

I believe thats all the questions I have at the moment. Thank you a bunch for taking the time to help me out. :)

(Idk if it makes any difference but I thought I should mention this grow will be done outdoors. I don't have the room in my house to grow indoors)
 

ShLUbY

Well-Known Member
Thank you so much for the in depth reply. A few follow up questions.

1. With canadian spagnum peat moss, is pH something I should be worried about? (This goes for the worm castings and other amendments as well)

compost is a great buffer for pH, and an all purpose fert usually has dolomite lime, oyster shell, or something else to help buffer pH.

2. With worm castings do I need to be worried about NPK values? If so then what is a good NPK value I should look for?

no

3. ^^ (Also you said worm castings were not something to cheap out on, with that being said is there a specific brand you would recommend that I would be able to get shipped from amazon or ebay?) I was wondering if this would be any good? https://www.horticulturesource.com/aurora-innovations-roots-organics-earth-worm-1-cu-ft-60-plt--p23716?gclid=CjwKCAiAyfvhBRBsEiwAe2t_i0OTzGVVTdAB1NC2jXi9iZkM3X3b60aFZyYVfg8Xb95EeqFTVc0ocxoCNcIQAvD_BwE

expensive, but likely a quality casting. never used their castings. when i used to order i would get them from WormPower in new york... but now i have a worm bin. best cheap investment I've ever made for my garden! saves me hundred of dollars

4. Reading from other users on here it seems the 3 most common used forms of rock dust are glacial, granite, and basalt. Which of these do you recommend the most? Or is there a different one thats less common but better?

i really like glacial, because it contains a mix of stones. the only thing i dislike about it is how fine most of them are. typically i get basalt because of the texture (more sand like than powder). there is also some scientific reasoning to use basalt but i'm not well versed on that subject.

5. You mentioned that the four amendments (peat, compost, drainage, minerals) make up your "base" When you say base what do you mean? (also you mention the peat should be "pre wetted" but then later you go on to say mix all the amendments and fertilizer together with some water. Could you elaborate on that some?

Base mix: the bulk portion of your soil before adding nutrients/amendments. this is a good starting point for a variety of plants, and then nutrition can be adjusted for specific plants if they require special needs. the base mix is a fairly nutrient poor medium, which is why we add nutrients/amendments. the base mix is your soil.

peat moss is a mess when dry (wear a dust mask), and expands when wet. you want to measure the expanded peat. plan on breaking it up, putting it in a tote, watering it, and turning it every so often until saturated. keep a lid on the tote to help raise humidity to hydrate it. it's a bitch to hydrate, but a great product.


6. Fertilizer confuses the shit out of me. I have read that cannabis needs high N in the veg stage, and high P & K for flowering. So my logic is if the plants need high N in the veg stage, I would buy a fertilizer for veg, and then later on give the plants a different fertilizer for flowering? But you say to mix the all purpose fertilizer with everything the peat, compost, drainage, and minerals. So with you recommending an "All purpose organic fertilizer" would it cover veg and flowering without needing to have two types of fert one for veg one for flower?

well there is truth and there is misconception to some of what you have read. you can use an all purpose with no issues, because the plant uses all of these nutrients, in different quantities, throughout the entire grow. the great thing about organic growing, is just having it in the soil is enough. the plant and microbes will take care of the rest. remember the plant can feed and grow itself, it does not need your help. it's done it for millions of years.

EDIT: i should elaborate a little bit at least. in this sort of living ecosystem, plants get their nutrient from organisms in the soil. organisms in the soil get food in the form of sugars from the plant in return. the nutrients you add to your soil are not available until broken down by organisms. so when the plant wants something, it will ask for it, it will be fetched by the organism that specializes in what is asked for, and it will be received! pretty cool eh?


7. For "All purpose organic fertilizer" what NPK should I look for? And to make things easier on me could you recommend or link an all purpose fertilizer?

https://www.amazon.com/Dr-Earth-Life-Purpose-Fertilizer/dp/B07B168GBV/ref=sr_1_3?ie=UTF8&qid=1547690953&sr=8-3&keywords=dr.+earth+organic+fertilizer

this is a solid product. you might even consider getting the the flower girl for later in the season as a topdress when the plants start taking on a noticeable stretch at the end of summer.


8. Also you never mentioned anything about compost teas, foliar feeding, topdressing etc. I'm assuming an all purpose organic fertilizer mixed in with the peat, compost, drainage, and minerals will provide all the nutrients needed from veg to flowering with only water needed? No nutes from time to time?

compost teas are unnecessary if your soil was properly composted (never stinky/foul) and remains properly moist ALL THE TIME. no wet/dry cycles. provide consistent amount of water, not too much (there should be no run off) and not too little (don't let the pots get light in weight). the compost in your soil has plenty of microbial life. now with that said, a compost extract from time to time would be fine. you simply rinse compost in a sieve with water into a catch bucket, and voila, compost extract. nice rich brown water full of microbes and fulvic acids (i know TMI haha). foliar feeding is unnecessary. topdressing can be beneficial.

ONE REALLY IMPORTANT NOTE: the surface of the soil should have a mulch on it at all times. a simple and effective mulch is bedding straw (from the farm store). cheap and effective. 1" layer is fine. this will help your soil retain moisture longer.

ANOTER NOTE: compost teas are tricky. without a microscope, there's no way to really quantify how good your tea really is. so I would say for you to just avoid it all together and use the compost extract method.


9. Is it safe to start from seed in this recipe? Or will it burn the plants?

this is a safe to use recipe for seeds. i have used it myself.

I believe thats all the questions I have at the moment. Thank you a bunch for taking the time to help me out. :)

(Idk if it makes any difference but I thought I should mention this grow will be done outdoors. I don't have the room in my house to grow indoors)
if you click the drop down quote box in this post, you will see your answers in blue. you are welcome
 
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kkt3

Well-Known Member
ShLUbY is one guy who’s advice should be put into motion!! There’s a few guys on RIU that know what they’re talking about, and he’s one for sure!!


Best thing you can do is start your own worm bin. You will start to use them for a bunch of things.

I topdress my girls at 2 and 4 weeks after 12-12, with about 3/4” fresh ewc. They are gold!!!
 

SG420

Active Member
if you click the drop down quote box in this post, you will see your answers in blue. you are welcome
"mix everything up and add some moisture so that it is wet but not sitting in a puddle of water. loosely cover it (a large tarp works great) and once a week mix it up to introduce fresh air."

can this be done in colder weather or do i need to wait for the spring solstice? if i wait until spring it will set me back a few weeks waiting for the soil to "cook"?
 

ShLUbY

Well-Known Member
"mix everything up and add some moisture so that it is wet but not sitting in a puddle of water. loosely cover it (a large tarp works great) and once a week mix it up to introduce fresh air."

can this be done in colder weather or do i need to wait for the spring solstice? if i wait until spring it will set me back a few weeks waiting for the soil to "cook"?
you absolutely can NOT do this in cold weather. this is a biologic process. cold temps will inhibit breakdown severely. if you're not composting very much soil, maybe you can do it indoors somewhere?
 

SG420

Active Member
you absolutely can NOT do this in cold weather. this is a biologic process. cold temps will inhibit breakdown severely. if you're not composting very much soil, maybe you can do it indoors somewhere?
thanks for clarifying!

> about how long should i "once a week mix it up" before its ready to use? keep in mind my location has high humidity and also high temperatures come summer

> you mentioned in another thread a method to whether or not i could tell if my native soil was okay to mix in with my soil recipe you gave me. does this also have to be checked in the spring or can i check the soil any time of the year? thank you shulb
 

ShLUbY

Well-Known Member
thanks for clarifying!

> about how long should i "once a week mix it up" before its ready to use? keep in mind my location has high humidity and also high temperatures come summer

> you mentioned in another thread a method to whether or not i could tell if my native soil was okay to mix in with my soil recipe you gave me. does this also have to be checked in the spring or can i check the soil any time of the year? thank you shulb
4-6 weeks is a proper composting time. if you have cooler temps it will take longer. if you have warmer temps it will take no more than 4 weeks.

you can check your native soil anytime so long as its not too frozen to dig haha. just make sure while you're digging to pay attention to the soil layers. the top 6" and lower than 6" are not always the same soil.
 
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