mycorrhizae with organics

[LadyLargely]

So, I've returned and had a good long read. I'm still of the opinion that 90% of the info here is highly scholastic and means little to the average gardner looking for simple, reliable methods of organically cultivating high-quality cannabis.

However! That does not mean we can't all benefit from this discussion. I will be coming in and asking about a number of the aspects discussed here, but for the moment one really leaps out at me

GanjaDin:

It seems you dedicate a lot of thought to the density and porosity of soil additives. As always, you put a lot of emphasis on measuring specific aspects. It almost seems like you are trying to 'calculate' the perfect medium consistency. I do not have the technical chops to talk about it that way, but it does lend itself to a personal philosophy of mine.

GD, would you agree that we should approach soil building just as we might approach building a composite?

The way I see it, we are starting with soil. Individual soil particles are mind-bendingly small. The mesh on it (especially high-quality compost) is tiny beyond belief. Going with the strategy of pushing air through my medium has caused me to address the tiny size and high density of compost particles.

My solution has been to build a medium that uses a variety of particle sizes in order to 'prop up' the tiny soil particles. Using additives with a successively larger mesh size I build up a platform to support the soil. My current strategy goes something like this:

Smallest mesh: Soil


Next largest: Vermiculite and Soil Sponge (powdered coconut husks)


Next largest: Chunky pearlite



Largest of all: Horticultural Coco



You get the idea. Small -> Big

This results in a super-low density medium that is suitable for pushing air through yet dense enough to support powerful colonies of beneficial fungus.



It works, but I have little evidence to tell me that. All I know is that when you pour water through it the runoff is almost completely clear. The vermiculite really 'grips' the soil particles and the other additives keep that from getting disturbed or carried away.

I've discovered what I think to be the best additive ratios through pure trial and error. Is there a more sceincy way to do this? Are there other additives out there that could help me but I'm not using? Could soil density/porosity somehow be calculated to find a medium with the highest density which can still have air pushed through it?

 

[maryjohn]

wow, in a surprising twist, lady largely shifted the topic to obbt.

 

[LadyLargely]

wow, in a surprising twist, lady largely shifted the topic to obbt.

Heh, wow, in a surprising twist maryjohn had a snide and not-at-all helpful comment for me!

If you check that post real quick you'll find "OBBT" was not mentioned once. The fact that you bring it up says a lot more about you than it does about me. Other than a brief mention of my particular desire to push air through the medium there was no OBBT-related material in there at all.

What I want to know is if there is a simple way of calculating soil density? I feel my way through things and now that I'm on ICmag I desire to add a little scientific back-bone to my touchy-feely methods. There seems to be a 'threshold' for having a medium that you successfully push air through. I would like to be able to calculate this threshold.

And the ensuing conversation could mean a lot to non-Bio Box gardeners. Proper soil density is critical to a successful microbialy-active organic medium. If you think the potential benefits of having my question answered could only be used in the interest of OBBT gardeners then you are much more small-minded than I thought.

Thanks for your help

 

[ganja din]

So, I've returned and had a good long read. I'm still of the opinion that 90% of the info here is highly scholastic and means little to the average gardner looking for simple, reliable methods of organically cultivating high-quality cannabis.

Hi. Great! I am very impressed you gave it/me another chance, thanks. I agree a lot of what I is not average, but any 'average' gardener can do what I do, and utilize the info I offer. I have no degree, I just like to read and study, I also try to pass on 'ivory tower' info into laymen terms for my friends, and myself...I'd rather read laymen terms (if accurate), than fancy ivory tower terms.

I may loose my Internet connection, if I do I will post soon. But a few quick points:

Bulk density should not be too 'bulky', this lower the % air porosity and would require a greater air flow from you compressor.

I can tell you how to measure % air porosity, % water porosity, % total porosity, bulk density, % moisture content, CEC and pH.

For one making their own soil I feel all those measurements are kinda important, especially % air porosity and pH.

RE: particle size: that is one of the most important considerations because it dictates the % air porosity and % water porosity, and VERY importantly the heights of the "perched water table".

Ideally particles will be 1/32-1/8", or better yet, 1/16-1/8". The reason is with many different sized particles will fit together making a 'solid' media. Small particles will fit in the air spaces between big particles, thus lowering the % air porosity and increasing the perched water table.

OK, gotta go, I offer you more info today when I have more time.

(for give typos, etc, I didn't have time to proof read)

 

[215 User]

The Sunland brand organic soil from OSH has this already mixed in.........
Used it for last 8 years & outshines all tha high priced/overrated name brand soils.
Less than $10 abag & worth every penny!

Simple organics with Max. results

 

[LadyLargely]

Ganja Din, I think get where you are going with all this, its starting to make sense.

Beyond the size and 'fluffiness' of soil additives I always look at how readily they take up moisture. I assume this must correlate with %water porosity. And overall air content (thus material vs atmosphere density) = %air porosity yes? Or is it something more like surface area?

I get what you mean by using grains of too many sizes leading to a really 'solid' mass. Bio Box gardeners in particular though need this effect to an extent. It keeps soil in place and prevents further compacting. We do not want our medium 'falling' down into our water table.

We combat the ill effects of multi-grain mediums by using irregular grain additives. Big chunky pearlite is this way, as is the very chunky compressed-block style coco coir. I know that type of choir is 'low grade' but when treated with boiling water in a kind of 'steam wash' it is possible to remove residual salts and turn the coco 'cubes' into magnificent coco hair clumps.

The hairy, springy nature of the finished medium resists compaction despite consisting of several grains. You can snag up a handful of it and squeeze it very hard. As soon as you let go it springs froward as if nothing had happened. The multi-grain medium may 'interlock' to an extent, but it seems to have the exact opposite effect to what you describe. As a side-effect of the ingredients an unusually low density is achieved.

I think its because you can't really call broken-down coco moss a 'particle'. Hairs do not behave like particles. I think something about the way the coco moss interacts with all the other non-hair-like ingredients is special.

Also, you say that the interlocking phenomenon is a problem with making a good "perched water table", whatever that is. I think Bio Box gardeners may be immune to that issue. By using a rock layer separate from our soil layer we set our water tables manually. The mega-low density of the materials we fill our water tables with coupled with the way we plumb our pots means that the only 'wet' bit of the medium is the rocky bit. The soil-containing bits always just stay uniformly 'moist'; right at that tipping point between perfect water saturation and the medium being 'too wet'.

But anyway, your calculation techniques sound excellent. I'm looking to re-engineer my medium next go-round and having that sort of knowledge at my disposal would be of enormous assistance.

 

[quadracer]

I realize you know but to avoid confusion, it is ectomycorrhizal which ‘in our knowledge’ associates with trees but some of these fruiting mushrooms (even ectomycorrhizal species) grow in fields (puffballs, agaric species like various meadow mushrooms) and there are species which can grow in compost, wood chip or straw richly amended soil (the Garden Giant Stropharia - rugoso-annulata; Shaggy Mane [mmmm] -coprinus comatus; Garden Oyster - Hypsizygus ulmarius;
All available in kits from www.fungi.com
I'm unsure of the other species but know that Shaggy Mane is mycorrhizal to trees. If I have misread let me know.

Na, the Shaggy Mane is saprobic, so it grows on debris/compost too.

There is also Clitocybe Nuda (blewit), that can be grown in compost. In fact, that is my goal for this season, to get some blewits from my compost.

 

[maryjohn]

Heh, wow, in a surprising twist maryjohn had a snide and not-at-all helpful comment for me!

If you check that post real quick you'll find "OBBT" was not mentioned once. The fact that you bring it up says a lot more about you than it does about me. Other than a brief mention of my particular desire to push air through the medium there was no OBBT-related material in there at all.

What I want to know is if there is a simple way of calculating soil density? I feel my way through things and now that I'm on ICmag I desire to add a little scientific back-bone to my touchy-feely methods. There seems to be a 'threshold' for having a medium that you successfully push air through. I would like to be able to calculate this threshold.

And the ensuing conversation could mean a lot to non-Bio Box gardeners. Proper soil density is critical to a successful microbialy-active organic medium. If you think the potential benefits of having my question answered could only be used in the interest of OBBT gardeners then you are much more small-minded than I thought.

Thanks for your help

just ribbin' you girl. I know you like it.

here's where I am now on adding mycorrhizae:

price to add: very cheap
benefits: questionable
risks: see "price to add"

what to do special when using mycorrhizae: nothing. ignore them, since Ganja Din pointed out we know nothing or next to nothing.

Ganja: thanks for the Vinny Pinto reference. Very much enjoying his pamphlet.

 

[LadyLargely]

Arrrg, over-reacted again

Don't know what it is about this thread that makes me so damn hostile. Its that bastard DrunkenMessiah; he traumatized me. I always get defensive when I feel like I'm surrounded by much bigger brains....

 

[maryjohn]

I didn't think you were hostile. Relax!

 

[Microbeman]

Na, the Shaggy Mane is saprobic, so it grows on debris/compost too.

There is also Clitocybe Nuda (blewit), that can be grown in compost. In fact, that is my goal for this season, to get some blewits from my compost.

What I meant is that, like you said it can be grown in a garden (which is why I said the kit is available) with compost but is also mycorrhizal to trees. I don't believe that any of the ectomycorrhizal mushrooms are obligate to particular hosts but there are some that will not grow in a foreign environ.

Anyway, you just repeated what I said; read it again.

 

[Microbeman]

Ganja: thanks for the Vinny Pinto reference. Very much enjoying his pamphlet.

MJ; I thought you knew about Vinny a long time ago

http://www.icmag.com/ic/showthread.php?t=103402&highlight=EM

This is far more revealing - we could work this one out to the point we had the major groups for sure.

EM stuff


found this site on EM



very informative

Vinny's website which Mr Fista posted is a good source of info on fermenting EM.

Link broke so I removed it.

 

[ganja din]

@ MM,

I was wrong in some info I gave you. It's best to use an incandescent light bulb because the photons are higher nanometers, more red. PnSB ideally respond to 700-1100 nanometers (wavelength). This also means the other info I provided about kelvins is wrong too. SOrry about that! Because lower K means more red, one would want ~3,000 K, or lower. I don't have the nanometer to kelvin conversion handy, sorry.

 

[ganja din]

Ganja Din, I think get where you are going with all this, its starting to make sense.

Good, I'm glad to help From you questions, you have prompted me to start a thread discussing the important issues when one builds a soilless media (I made a typo on my last post to you by writing "soil"). You are correct that my goal is to calculate the ideal soilless media for cannabis, and I think I achieved that goal, about a year ago I stopped working on the idea because I was happy with my results. But, I'd be very happy to post up some good info for you and others.

Beyond the size and 'fluffiness' of soil additives I always look at how readily they take up moisture. I assume this must correlate with %water porosity.

No, not really.

Check out the following link for info from Cornell U. about porosity:
http://web.archive.org/web/20070610...artment/faculty/good/growon/media/poros2.html

• Total porosity (% total porosity) = total pore volume / container volume

• Aeration porosity (% air porosity) = aeration pore volume / container volume

• Water-holding porosity (% water holding porosity) = total porosity - aeration porosity

And here is more info from Cornell U., I quoted it below for reference:
(the italicized words were changed from the bold Cornell U. used)
http://web.archive.org/web/20070808...tment/faculty/good/growon/media/porosity.html

"POROSITY:

The amount of pore space in container media is a critical physical characteristic which influences water and nutrient absorption and gas exchange by the root system. Pore space is related to the shape, size, and arrangement of media particles. Aeration porosity and water-holding capacity are two critical physical attributes of container media.

Total porosity reflects the total pore space present in growing media; it represents the percentage of the container media volume which is not occupied by solid media particles. Porosity is determined by media particle size and the extent to which the particles can be compressed. Total porosity is the sum of the aeration and water-holding porosity of media and should comprise over 50% of the container media volume.


Irrigating media to the point of saturation fills the total pore space with water. As the media drains by the force of gravity, smaller pores remain filled with water while larger pores empty and fill with air. When all water has drained from the large pores, the amount of water remaining in the medium's small pores is referred to as container capacity. Aeration porosity is comprised mainly of the large pore spaces, macropores, which drain water freely as a result of gravitational forces and remain filled with air after media saturation and drainage.


For adequate gas exchange, aeration porosity should constitute at least 15%, but ideally, 20-35% of the media volume. Water retaining micropores should comprise 20-30% of the media volume. Water held in even smaller pores is not easily extracted by the plant. Conditions under which these very small spaces are the only pores retaining water often result in some stomatal closure and wilting. As the media dries and water is available only from the smallest pores, significant wilting can occur.

For sufficient gas exchange, drainage, and water-holding capacities, the proper proportion of macropores to micropores is necessary.The type of container media mix used determines the amount of macropores and micropores in the media. In addition, the size arrangement of pores is important in the ultimate water-holding capacity of the mix. A peat-sand mix contains a greater number of large and medium sized pores than a bark-sand mix. Media containing the greatest amount of medium-sized pores has the potential to hold more readily available water."

(Media composed of larger particles has a greater percentage of aeration porosity)

(Media composed of smaller particles has a greater percentage of water-holding porosity.)

I get what you mean by using grains of too many sizes leading to a really 'solid' mass. Bio Box gardeners in particular though need this effect to an extent. It keeps soil in place and prevents further compacting. We do not want our medium 'falling' down into our water table.

That's the point, with the proper particle size they will not 'fall', nor 'interlock', please see the previous two pics I uploaded.

"...water table". Can you explain that please? I read your thread and it seems like you have soilless media over hydroton grow rocks which are in a container filled with water? Is the water aerated? I think I read you leave the water there for a while? You had a Q of weather water like that would be similar to ACT. My fear is no. Unless you can keep the DO (Dissolved Oxygen) above 6, and change the water every 3 days (max!), every 24-48 hours would be 'safer'.

We combat the ill effects of multi-grain mediums by using irregular grain additives. Big chunky pearlite is this way,

The problem with perlite is it will 'float' to the surface, and it's a pretty crappy amendment IMO. In place of perlite I would HIGHLY suggest "Axis regular". I will write about it in the up coming soilless media building thread. Here some axis info for now:

Axis: http://www.axisplayball.com/AXIS.htm

Hort. Applications: http://www.epminerals.com/landscape-copy.html


Axis "regular":

• Large pores (average pore size for is +/-0.9 micron...ideal size!)

• Very low water tension

• High water release rate (90%)

• Particle size = 70% of axis "regular" is 1/8"

• CEC = ~27 meq/100g (perlite is ~1.2-3.5 meq/100g)

Sources:

• Western US:

EnviroTech Soil Solutions, Inc. (based in PNW) http://www.axisplayball.com/AXIS.htm
Call 866-546-3722

• Eastern/Southen/Northern US:

EaglePicher Filtration & Minerals, Inc. (they are the ones who make Axis) http://www.epcorp.com/EaglePicherInternet/Filtration_Minerals/
Call 775-824-7600

• Western Canada [maybe Eastern too]:

Turf Canada

NOTE:
Make sure you get Axis "regular", it is about $15.00 per cu ft(25lbs)...not too expensive when it's only 30% of the mix and it's so beneficial and it means you don't have to by perlite and/or vermiculite...hell, you could reuse the mix indefinitely if you choose

as is the very chunky compressed-block style coco coir. I know that type of choir is 'low grade' but when treated with boiling water in a kind of 'steam wash' it is possible to remove residual salts and turn the coco 'cubes' into magnificent coco hair clumps.

The hairy, springy nature of the finished medium resists compaction despite consisting of several grains.

As far as I understand, that will not 'help', it makes matter worse by having very large particle size. It's important to use some type of 'water holding' amendment when designing a soilless media. However, peat, coir, etc, shouldn't be more than 5-10% (max) of total media (volume/volume).

Cannabis has 'fibrous' roots which can withstand lower % air porosity than fine, or 'fleshy' roots.

Here are what I consider good 'goals' for cannabis soilless media:

• % air porosity = 25-40%

• % water porosity (% water holding porosity) = 15-25%

• % total porosity = >50%

You can snag up a handful of it and squeeze it very hard. As soon as you let go it springs froward as if nothing had happened. The multi-grain medium may 'interlock' to an extent, but it seems to have the exact opposite effect to what you describe. As a side-effect of the ingredients an unusually low density is achieved.

Hummm. I think maybe what is apparently happening on a macro scale (naked eye) and micro scale are two different things. Here's some bulk density info. This is from the now defunct Cornell U. Soil Science department. I have downloaded the whole site, but it is also at "way back machine"

• Bulk density:

http://web.archive.org/web/20080521...partment/faculty/good/growon/media/bulkd.html

• Bulk density of some mediums:

http://web.archive.org/web/20080521...tment/faculty/good/growon/media/bulkdtbl.html

I think its because you can't really call broken-down coco moss a 'particle'. Hairs do not behave like particles. I think something about the way the coco moss interacts with all the other non-hair-like ingredients is special.

Sorry I don't agree. Please see earlier comments.

Also, you say that the interlocking phenomenon is a problem with making a good "perched water table", whatever that is. I think Bio Box gardeners may be immune to that issue. By using a rock layer separate from our soil layer we set our water tables manually.

Hummm, I think maybe not. Do you water via drench method? Ie. pour water over media? Is the media in a container with a bottom? Or is the media on the rocks? How high is the water in the rocks?

Here's some info on perched water table (PWT), and a MUST read for building soilless media in general. PWT is pretty much the level (height) of the media at which the water will 'perch', or 'stall', while the water below is being absorbed or washed away. So, depending upon your rock/water situation, you might need to think about PWT.

The following link is to a ongoing post is by "Al" (aka "tapla") who is on gardenweb. This is a very nice and informative post on building media. I believe Al may have read the info from Cornell U. (I just posted) and other sources I've seen when he developed his methods...needless to say I agree with a lot of his post.

A very important point I want to stress is Al's explanation and reasoning for NOT adding a 'so-called' "drainage layer" to containers. While the Cornell U. page say to add a course material (broken ceramic, etc) to help drainage I disagree. I think Al is spot on in his reasoning...I don't add a drainage layer, my whole container is filled with exactly the same media.

Note:

• Al doesn't advocate organics as a matter of course, and uses chemical inorganic salts mostly for fertilizer.

• Al is trying to make media with around >40% air porosity, for plants with 'fleshy' roots, not the 'fibrous' roots of the cannabis plant.

• Keep that in mind while reading the following excellent information...

"Container Soils - Water Movement and Retention - A Discussion About Soils"
by Al
http://forums2.gardenweb.com/forums/load/contain/msg0715434425632.html

The mega-low density of the materials we fill our water tables with coupled with the way we plumb our pots means that the only 'wet' bit of the medium is the rocky bit. The soil-containing bits always just stay uniformly 'moist'; right at that tipping point between perfect water saturation and the medium being 'too wet'.

That's a main issue. What does "moist" mean? In terms of quantification? The issues which control the 'moistness' would be % air porosity, % water holding porosity, media internal and external pore size, particle size (ie. interlocking).


If I were you, first thing today I would measure your soilless media % water content, that will tell you the % of moisture in the total media. You want ideally 50-55% moisture content all the time. NEVER lower than 30%, but roots can extract water from media up to about 30% moisture content. Of course, % moisture content lower limits depends upon the pore size and "water release rate" of amendments making the media. Anywhere from 45-60% moisture content, after excess water has drained away, is fine. For most aerobic microbes to thrive the ideal % moisture content is 50-55%, not lower then 45% and not over 60%.

At the bottom I will link to easy method to test % moisture content. It takes 24 hours, an oven, or better yet a food dehydrator, a scale, tin foil, notepad with pen and calculator.

But anyway, your calculation techniques sound excellent. I'm looking to re-engineer my medium next go-round and having that sort of knowledge at my disposal would be of enormous assistance.

Some notes:

I would suggest the use of straw based compost in place of the coco coir. I like to use 2-4% freash vermicast with 2-4% straw based compost in place of peat moss or coco coir.

On the topic of particle size and solless media lifetime. The roots, along with glue like substances from microbes (ex. "bio-film", etc), and fungal hyphae/mycelium should help hold particles in place.

This is why I *HIGHLY* suggest a 'no-till' approach. For example, one could have eight containers of soilless media. Four he/she will use to grow cannabis and a healthy microherd. The other four containers will get a 'cover crop' like Sudan grass, mazes, etc. The cover crop is to interface with the microherd and keep the solless media alive. After the cannabis harvest the grower would cut the cannabis stalk down but leave the roots and media alone. The grower then takes the four 'cover cropped' containers of soilless media and cuts down the grass, then transplanting in well established cannabis clones. The four just harvest containers are cover cropped so the microherd can start breaking down the root system of the harvested cannabis. Employing AEM at this point is very wise, the PnSB can speed dead cannabis root decay through enzymes, etc. And on goes the cycle...


Pore size:
This effects CEC and water tension within the pores and on the surface of media particles. A high level of water tension makes it harder for roots to extract the water held in the pores of the media particles. Even if some media has the best CEC in the world, if it also has high water tension the CEC doesn't mean sqat.

There is a relationship between pore size and water tension. The smaller the pores the higher the water tension. Ideally, a pore size of 1 micron is what you want for low water tension.

The "water release rate" refers to the % of total water retained by the particle which is available for the plant. If a media particle has a water release rate of 50% that means only 50% of that water held by the particle is available to the roots...the rest of the water (the other 50%) is held so tightly (internally) that the roots can not extract it.

Peat:

• Med to large pores

• Medium water tension

• High water release rate (93%)

• High internal porosity (eg. roots also penetrate individual peat particles to access the water stored within, then they can extract it)

Two MUST reads:

• "Media: Rooted in Success"

[SIZE=-1]Cornell Cooperative Extension
Dept. of Floriculture and Ornamental Horticulture, Cornell University © 1997[/SIZE]
(see "contents"; I suggest downloading this while website with "HTTrack" because you it might disappear even from "way back machine")
http://web.archive.org/web/20080521...partment/faculty/good/growon/media/index.html

• "Container Soils - Water Movement and Retention - A Discussion About Soils" (part IX)

by Al
http://forums2.gardenweb.com/forums/load/contain/msg0715434425632.html






How-To's:



Calculate % air porosity, % water holding porosity and % total porosity:
(this takes a bit of practice and patience, and 2 litter pop bottles. Or you can send samples off to a lab for ~$25-50 to pay them for tests. I use a Ranco food dehydrator set at 105F for 24 hours to dry samples)

• "Determining media porosity"

http://web.archive.org/web/20070610...artment/faculty/good/growon/media/poros2.html

• "Calculating total porosity, aeration porosity, and water retention of growing media or soil"

http://web.archive.org/web/20070702001035/http://www.treeco.biz/Keenan/calculating+pore+space.htm






Calculate CEC:
(A lab is best here IMO. Here is CEC info: http://web.archive.org/web/20070808...epartment/faculty/good/growon/media/ions.html )

• "Recommended Methods for Determining Soil Cation Exchange Capacity"

by Donald S. Ross
http://web.archive.org/web/20080522105150/http://www.analytika.gr/METHODS/SOIL/cec.htm

• "Potential pH"

If composting one can use the Luebke families method of finding the difference between the actual pH and the "potential pH" (using acids) which correlates to an increase or decrease in CEC. Mr. Diver wrote about the method in his paper on "Controlled Microbial Composting", which I uploaded on a previous page.






Calculate pH:
(It's wise to download this whole site too, in case it goes down like the other Cornell U. site)

• "Monitoring Compost pH"
  http://compost.css.cornell.edu/monitor/monitorph.html

Calculate % moisture content:
(aka "gravimetric" moisture content. I use my food dehydrator for this too)

• "Moisture Content"
  by Nancy Trautmann and Tom Richard
  http://compost.css.cornell.edu/calc/moisture_content.html

HTH

 

[ganja din]

And Lady,

I must ask, why forced air? It's not very organic if you consider how the compressor is powered. Nor very portable. And I don't imagine many people will adopt your methods due to cost constraints, and more so, convince issues. But, if you like it and it works well for you then I am stoked for you. I always like to see new ideas in action!

What I don't understand is why you don't relay upon the respiration of a healthy microcherd, and temperature convection to ensure air flow into/out of the media.

If one achieves a high % air porosity of say 30-40%, then the microbial respiration alone should offer plenty of fresh O2. And if you put the containers on a screen, while using a 'grow bag', plenty of air would reach the outside of the media, so the microbes can use it.

Just my thoughts about ideal solliess media and microherd vs. forced air.

HTH

 

[ganja din]

bad typo!

bad typo!

After my re-re-re-re-read:

I noticed I made a bad typo, I am tired and was working off my old-ish notes and I think I used the most old-ish copy. Ha. Well,that doesn't matter I guess...

The typo:

Ideal particle size = 1/8 inch to 1/4 inch

Not size of 1/32 inch to 1/8 inch (that's baaad)

Reasons:

Smaller than 1/8 inch particle size will stop water from draining thus creating, or raising the perched water table (PWT).

Larger then 1/4 inch particle size and microbial communities have a hard time forming. Especially bacteria, the gaps between particles hinder the formation of bacterial colonies and bio-film.

Re: coir and peat:
They both have particles smaller then 1/8 inch, and they compress which further reduces the effective particle size for % air porosity.

Sorry about that. So now its correct, and easier to screen!

I have used, and will use again once fully organic (again; but not till I'm in a med state):

(Screened from 1/8 inch to 1/4 inch)

~50-60% Aged pine bark fines

~25-35% Axis regular

~2-4% Straw based compost (fungal and bacterial) [not screened]

~2-4% Vermicast [not screened]

Zeolite powder (for CEC)

Azomite (volcanic rock powder for microbes and eventually the plant)

Calcitic lime (micronized for pH and Ca)

HTH and if anyone sees errors please let me know! Thanks

 

[maryjohn]

MJ; I thought you knew about Vinny a long time ago

I have been afraid to get too far into EM lore due to kookiness, but I find him 9 parts serious or just reporting and only 1 part kooky.

I really like the recipes. been gargling with regular AEM no problem and it tastes great. very clean. however I have also started a grape batch and ran out of molasses so it's barley malt.

 

[ganja din]

A few more things:

I forgot to give you info on measuring bulk density, and an easier method to measure % air porosity at the same time (essentially). The good part is one can use the % air porosity to calculate the other porosities, all much more simply then the other methods I provided from Cornell U. The catch is you need to sacrifice 5 gallons of what you are measuring.

Once one has the % air porosity, using the equations I posted above should work fine. Though I have yet to use this method, I just thought of it! I will try thos when I have time next week. If anyone uses this method to calculate all the porosities can you please post you results/thoughts? Thanks

Calculate Compost Bulk Density
http://www.puyallup.wsu.edu/soilmgmt/BulkDensity.htm

Calculate bulk density and % air porosity
http://dbwww.essc.psu.edu/dbtop/doc/statsgo/meth_bd_poros.html

I think that's all for now. HTH

 

[ganja din]

Hey lady,

I thought it would be helpful if I tried to distill all the info I posted into a single, short post as one soilless mix to rule them all! (Haha, I like Lord of the Rings)

Please take no offense. Here is what imo is ideal for cannabis. IMO, all pre-made soilless media are FAR from ideal, the same goes for every DIY soilless media mix for cannabis I have ever read. Those which rely upon peat or coir, or other material with lots of particles smaller then 1/8 inch, or that compresses easily, are far from ideal.

Cannabis roots are fibrous, so they can withstand a lower % air porosity than fleshy roots.

ideal for cannabis roots:

(No drainage layer! Ex. Layer of rocks, perlite, etc, at bottom of container)

- % air porosity = 25-40%

- % water holding porosity = 15-25%

- % total porosity = >50%

- % moisture content = 50-55% (45-60% is ok)

- CEC = ~ >50 meq/100g

- pH = 5.5 to 6.5

- Water release rate = should be good, >60 or 70%

- Media particle pore size = 1 micron (< and >1 micron is ok)

- Particle size = 1/8 inch to 1/4 inch

Reasons for screened particle size:

Smaller than 1/8 inch particle size will stop water from draining thus creating, or raising the perched water table (PWT).

Larger then 1/4 inch particle size and microbial communities have a hard time forming. Especially bacteria, the gaps between particles hinder the formation of bacterial colonies and bio-film.

Re: coir and peat: They both have many particles smaller then 1/8 inch, and they compress which further reduces the effective particle size for % air porosity, thus creating, or increasing PWT.

I have used this mix with great success:

IMO this is the best mix for cannabis, that is, when apply organic ferts at watering (ex. hydrolyzed fish, humic and fulvic acids, kelp extracts, etc). I have yet to send the soilless media for bio-assay, but from my research and expereince the mix I propose is a fine environ for soil food web organisms and nutrient cycling.

(Screened from 1/8 inch to 1/4 inch)

- 50-60% Aged pine bark fines

- 25-35% Axis regular (pre-rinsed)

- 2-4% Straw based compost (fungal and bacterial) [not screened]

- 2-4% Vermicast [not screened]

- Zeolite powder (for CEC)

- Azomite (volcanic rock powder for microbes and eventually the plant)

- Calcitic lime (micronized for pH and Ca)

- Dolomitic lime (micronized for pH and Mg)

- Tween 80 as surfactant when initial moistening media.

HTH

 

[ganja din]

@ all:

I want to fix a typo I made. I wrote that Siegfried Luebke has a database of over 3600 different bacterial enzymes. That's not correct, sorry. Siegfried Luebke cataloged over 3600 different microbial enzyme reactions, many of which mineralize rock powder, etc.