This was touched on briefly in this thread: https://www.icmag.com/ic/showthread.php?t=25611

Here's a friend's explanation of why he doesn't mix his fertilizers globally in his soil mix but instead creates substrate layers and "hot spots."

Thought it might spark a little discussion.


Mixing your ammendments "globally" and what I mean by that is throughout, your mix, put's your plants in a very simple 2 dimentional situation; member the roots are alive, evolved, etc.... If you "smother" them with a two dimentional environment (globally mixing all your nutes) you FORCE them away from doing what they do best, find and absorb foodz! Find, being a key word

Ya know how mother earth is a mass of layers, "build" each container, layer it, put spots of stuff in amounts perhaps tripling what good sense would tell you is good. I shit you not amigo.

Think like the plant, when it finds a super hot N source what does she do? She does what she is evolved to do, her roots adapt at THAT LOCATION to duplicate root cells SPECIFIACLLY desingned to feast on such a rich find. Localize your major nutes within zones, rule of thumb is the longer release x power of release = lower in the container.

I top dress my flowering plants prolly 2 - 3 times after 12/12 with a mixture of 50% bat guano (High P) and 50% earthworm castings cut in half with fine grade vermiculite. Deadly deadly wicked trick homeskillet

So don't just read this shit fingster, from me to you man, get this. Gotta think "Chaos" man

- REv

very interesting, i'll give this a try. i love the idea of giving the roots "options" to choose from, it makes sense that a plant will prefer to actively seek out what it needs as it grows, rather than being force fed. i'm imagining handfuls of chopped up green-manure crops like alfalfa and comfrey "placed" in the lower portions of the pots.

The guy's plants speak for themselves. He has a few decades of outdoor experience and serious hydro experience... and until a few years ago, he was 100% sold on the idea that soil could never match hydro in growth rate or yield. Woulda bet his right arm on it, probably.

But now, after a couple years dialing in his organic soil skills and really tapping into this idea of letting the plant search out super-nutrient-dense patches/layers in the soil, he says he's getting really close already to matching the growth rate of hydro.

[muddy waters]

personally i think the idea makes much more sense applied to outdoor cultivation. like the old jamaican tactic of planting a bean and burying a fish right next to it. but not everything about natural processes outdoors can be replicated successfully in containers indoors.

for me, it's mainly the threat of things heating up, going anaerobic, or extreme pH that make me distribute everything evenly in the media. it may be worth a try replicating this more natural distribution but i have a hard time understanding why this would actually increase the rate of growth. i'd have to see that to believe it.

[zamalito]

We should remember that most varieties of cannabis have underwent centuries and sometimes millenia of domestication for monoculture cultivation so simulating the most wild environment possible is not always best. However beneficial bacteria and fungi have not. Personally as far as soil is concerned I try to think in terms of what benefits the beneficials more than what the roots want. Simultaneously I try to simulate the cultivation conditions for which the strain was bred to do best. Though many strains Some strains thrive in hydro some strains need biotics in the root zone. Some strains can't handle intense sunlight and stop growing above 80 degrees some strains won't form a potent flower without sunlight.

Originally Posted by muddy waters

or me, it's mainly the threat of things heating up, going anaerobic, or extreme pH that make me distribute everything evenly in the media. it may be worth a try replicating this more natural distribution but i have a hard time understanding why this would actually increase the rate of growth. i'd have to see that to believe it.

I'd tell you to try it before you judge it, but you don't even need to. There are folks at www. unleashthegreen .com doing it already. It takes a little bit of faith to just take another grower's word for it, but rolanterroy is the grower there who has made some real breakthroughs with this stuff and claims to be getting very close to the performance he's seen in hydro in his 25 years of breeding and growing. Go check it out and see what you think.

I am still left wondering what conditions exist outdoors that make it optimal to have nutrients sitting in varying concentrations that do not exist indoors. The fact that growing in containers indoors is different than growing in the ground outdoors is certainly true, but also pretty general. Specifically how is it different in ways that would relate to the nutrient concentrations in the soil?

[muddy waters]

there's a huge ecological difference, that is, the way that organisms interact with the environment outdoors is different than the way they interact indoors. outdoors you most likely have a much greater variety and overall population of beneficial micro-organisms, meaning that the decomposition and bio-availability of these concentrated nutes will probably be quicker. earthworms will also facilitate this, unlike in an indoor container grow. additionally you have the enormous thermal mass of the soil to offset any localized hot spots from raw high N manures. you have a nearly infinite area for roots to grow, meaning that if an anerobic or pathogenic zone develops the roots can avoid it without much consequence.

also culturally, outdoors you probably prepare your soil in advance, say, in the fall before a spring planting or at least several weeks before the last frost or before transplant. indoors it would be both a waste of space and/or unsanitary to leave, say, raw manure buried in soil in a container for a couple weeks before planting. indoors, i would want the quickest possible bio-availability of my organic amendments, and therefore i do not want to risk, say, a highly alkaline patch of pure bone meal which is unsuitable for nitrifying and other bacteria which cannot tolerate high pH. i don't doubt that eventually that clump of bone meal would be available to the plant, but in the name of efficiency, i don't think it would be a wise way of providing it to the plant. this is especially true for those of us using smaller containers. in a larger tub i could see this method paying dividends, especially at the end of a longer growth cycle. i don't veg at all and i use small containers, so this method doesn't seem ideal, that's all.

but this is all theoretical and i don't doubt at all that some people have mastered this type of culture. i always thought the rate of growth in hydro was directly attributable to the level of oxygen in the rhizosphere, for as you know, in an oxygen saturated environment the plant cell walls in the roots are practically an open floodgate for nutrient uptake. decrease the oxygen and nute uptake slows down.

[zamalito]

I agree whole heartedly muddy. Besides I don't see how placing balls of guano several inches below the soil surface is replicating nature. In most environments the nutrient (fecal matter plant matter etc) lands on the soils surface and is evenly carried down by rain and worms. I also am not aware of any research saying that cannabis roots develop specialized functions other than those that take in water and nutrient and those that transport nutrient. If anyone knows of this research I'd be very interested in reading it.

if the food is evenly distributed the roots will distribute evenly. all the roots will be feeding, and the whole container can fill with roots.

All good stuff, folks. Thanks.